No-Till: North Dakota Research Emphasis

Introduction of no-till into North Dakota soil management systems has raised many questions relative to performance under present cropping or climatic conditions. A number of long term cooperative research projects were established in 1977 to answer these questions and set some guidelines for no-till production systems. The areas of research emphasis at various experiment stations are discussed along with preliminary results on one year's data

Sugarbeet Production Under Reduced Tillage Prospects And Problems

A study was initiated in the fall of 1977 to obtain base line data on the applicability of reduced tillage sugarbeet production in the Red River Valley. Three reduced tillage systems were compared to a conventional system which consisted of fall plow plus secondary tillage. Results indicated warmer early spring soil temperatures, better seedling emergence, lower ground-level wind speed and no significant yield loss under reduced tillage as compared to the conventional system

Study of fuel cells using storable rocket propellants Final report, 18 Aug. 1965 - 23 Jun. 1969

Operating fuel cells on gaseous nitrogen tetroxide and aerozine 5

Lanthanum tungstate membranes for H-2 extraction and CO2 utilization: Fabrication strategies based on sequential tape casting and plasma-spray physical vapor deposition

[EN] In the context of energy conversion efficiency and decreasing greenhouse gas emissions from power generation and energy-intensive industries, membrane technologies for H-2 extraction and CO2 capture and utilization become pronouncedly important. Mixed protonic-electronic conducting ceramic membranes are hence attractive for the pre-combustion integrated gasification combined cycle, specifically in the water gas shift and H-2 separation process, and also for designing catalytic membrane reactors. This work presents the fabrication, microstructure and functional properties of Lanthanum tungstates (La28-xW4+xO54+delta, LaWO) asymmetric membranes supported on porous ceramic and porous metallic substrates fabricated by means of the sequential tape casting route and plasma spray-physical vapor deposition (PS-PVD). Pure LaWO and W site substituted LaWO were employed as membrane materials due to the promising combination of properties: appreciable mixed protonic-electronic conductivity at intermediate temperatures and reducing atmospheres, good sinterability and noticeable chemical stability under harsh operating conditions. As substrate materials porous LaWO (non-substituted), MgO and Crofer22APU stainless steel were used to support various LaWO membrane layers. The effect of fabrication parameters and material combinations on the assemblies' microstructure, LaWO phase formation and gas tightness of the functional layers was explored along with the related fabrication challenges for shaping LaWO layers with sufficient quality for further practical application. The two different fabrication strategies used in the present work allow for preparing all-ceramic and ceramic-metallic assemblies with LaWO membrane layers with thicknesses between 25 and 60 mu m and H-2 flux of ca. 0.4 ml/min cm(2) measured at 825 degrees C in 50 vol% H-2 in He dry feed and humid Ar sweep configuration. Such a performance is an exceptional achievement for the LaWO based H-2 separation membranes and it is well comparable with the H-2 flux reported for other newly developed dual phase cer-cer and cer-met membranes.ProtOMem Project under the BMBF grant 03SF0537 is gratefully acknowledged. Furthermore, the authors thank Ralf Laufs for his assistance in operating the PS-PVD facility. Dr. A. Schwedt from the Central Facility for Electron Microscopy (Gemeinschaftslabor fur Elektronenmikroskopie GFE), RWTH Aachen University is acknowledged for performing the EBSD analysis on the PS-PVD samples.Ivanova, ME.; Deibert, W.; Marcano, D.; Escolástico Rozalén, S.; Mauer, G.; Meulenberg, WA.; Bram, M.... (2019). Lanthanum tungstate membranes for H-2 extraction and CO2 utilization: Fabrication strategies based on sequential tape casting and plasma-spray physical vapor deposition. Separation and Purification Technology. 219:100-112. https://doi.org/10.1016/j.seppur.2019.03.015S100112219A.A. Evers, The hydrogen society, More than just a vision? ISBN 978-3-937863-31-3, Hydrogeit Verlag, 16727 Oberkraemer, Germany, 2010.Deibert, W., Ivanova, M. E., Baumann, S., Guillon, O., & Meulenberg, W. A. (2017). Ion-conducting ceramic membrane reactors for high-temperature applications. Journal of Membrane Science, 543, 79-97. doi:10.1016/j.memsci.2017.08.016Arun C. Bose, Inorganic membranes for energy and environmental applications, Edt. A. C. Bose, ISBN: 978-0-387-34524-6, Springer Science+Business Media, LLC, 2009.M. Marrony, H. Matsumoto, N. Fukatsu, M. Stoukides, Typical applications of proton ceramic cells: a way to market? in: M. Marrony (ed.), Proton-conducting ceramics. From fundamentals to applied research, by Pan Stanford Publishing Pte. Ltd., ISBN 978-981-4613-84-2, 2016.Di Giorgio, P., & Desideri, U. (2016). Potential of Reversible Solid Oxide Cells as Electricity Storage System. Energies, 9(8), 662. doi:10.3390/en9080662A.L. Dicks, D.A.J. Rand, Fuel cell systems explained, ISBN: 9781118613528, John Wiley & Sons Ltd., 2018.Zheng, Y., Wang, J., Yu, B., Zhang, W., Chen, J., Qiao, J., & Zhang, J. (2017). A review of high temperature co-electrolysis of H2O and CO2to produce sustainable fuels using solid oxide electrolysis cells (SOECs): advanced materials and technology. Chemical Society Reviews, 46(5), 1427-1463. doi:10.1039/c6cs00403bGötz, M., Lefebvre, J., Mörs, F., McDaniel Koch, A., Graf, F., Bajohr, S., … Kolb, T. (2016). Renewable Power-to-Gas: A technological and economic review. Renewable Energy, 85, 1371-1390. doi:10.1016/j.renene.2015.07.066Woodhead publishing series in energy, Nr. 76, Membrane reactors for energy applications and basic chemical production, Edt. A. Basile, L. Di Paola, F.I. Hai, V. Piemonte, by Elsevier Ltd, ISBN 978-1-78242-223-5, 2015.Morejudo, S. H., Zanón, R., Escolástico, S., Yuste-Tirados, I., Malerød-Fjeld, H., Vestre, P. K., … Kjølseth, C. (2016). Direct conversion of methane to aromatics in a catalytic co-ionic membrane reactor. Science, 353(6299), 563-566. doi:10.1126/science.aag0274Malerød-Fjeld, H., Clark, D., Yuste-Tirados, I., Zanón, R., Catalán-Martinez, D., Beeaff, D., … Kjølseth, C. (2017). Thermo-electrochemical production of compressed hydrogen from methane with near-zero energy loss. Nature Energy, 2(12), 923-931. doi:10.1038/s41560-017-0029-4J. Franz, Energetic and economic analysis of CO2 retention in coal gasification power plants by means of polymer and ceramic membranes (dissertation, German), Ruhr-University Bochum, Germany, Shaker Verlag, 2013.Franz, J., & Scherer, V. (2011). Impact of ceramic membranes for CO2 separation on IGCC power plant performance. Energy Procedia, 4, 645-652. doi:10.1016/j.egypro.2011.01.100E. Forster, dissertation, Thermal stability of ceramic membranes and catalysts for H2-separation in CO-shift reactors, Energy and Environment Band, vol. 284, ISBN 978-3-95806-084-5, RUB 2015.Escolástico, S., Stournari, V., Malzbender, J., Haas-Santo, K., Dittmeyer, R., & Serra, J. M. (2018). Chemical stability in H2S and creep characterization of the mixed protonic conductor Nd5.5WO11.25-δ. 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Synthesis and hydrogen permeation properties of asymmetric proton-conducting ceramic membranes. Solid State Ionics, 176(35-36), 2653-2662. doi:10.1016/j.ssi.2005.07.005Kniep, J., & Lin, Y. S. (2010). Effect of Zirconium Doping on Hydrogen Permeation through Strontium Cerate Membranes. Industrial & Engineering Chemistry Research, 49(6), 2768-2774. doi:10.1021/ie9015182LIANG, J., MAO, L., LI, L., & YUAN, W. (2010). Protonic and Electronic Conductivities and Hydrogen Permeation of SrCe0.95-xZrxTm0.05O3-δ(0≤x≤0.40) Membrane. Chinese Journal of Chemical Engineering, 18(3), 506-510. doi:10.1016/s1004-9541(10)60250-9Xing, W., Inge Dahl, P., Valland Roaas, L., Fontaine, M.-L., Larring, Y., Henriksen, P. P., & Bredesen, R. (2015). Hydrogen permeability of SrCe0.7Zr0.25Ln0.05O3− membranes (Ln=Tm and Yb). Journal of Membrane Science, 473, 327-332. doi:10.1016/j.memsci.2014.09.027Oh, T., Yoon, H., Li, J., & Wachsman, E. D. (2009). Hydrogen permeation through thin supported SrZr0.2Ce0.8−xEuxO3−δ membranes. Journal of Membrane Science, 345(1-2), 1-4. doi:10.1016/j.memsci.2009.08.031Hamakawa, S. (2002). Synthesis and hydrogen permeation properties of membranes based on dense SrCe0.95Yb0.05O3−α thin films. Solid State Ionics, 148(1-2), 71-81. doi:10.1016/s0167-2738(02)00047-4Escolástico, S., Ivanova, M., Solís, C., Roitsch, S., Meulenberg, W. A., & Serra, J. M. (2012). Improvement of transport properties and hydrogen permeation of chemically-stable proton-conducting oxides based on the system BaZr1-x-yYxMyO3-δ. RSC Advances, 2(11), 4932. doi:10.1039/c2ra20214jH. Matsumoto, T. Shimura, T. Higuchi, T. Otake, Y. Sasaki, K. Yashiro, A. Kaimai, T. Kawada, J. Mizusaki, Mixed protonic-electronic conduction properties of SrZr0.9−xY0.1RuxO3−δ, Electrochemistry, 72(12), 861–864.M.E. Ivanova, S. Escolático, M. Balaguer, J. Palisaitis, Y.J. Sohn, W.A. Meulenberg, O. Guillon, J. Mayer, J.M. Serra, Hydrogen separation through tailored dual phase membranes with nominal composition BaCe0.8Eu0.2O3−δ:Ce0.8Y0.2O2−δ at intermediate temperatures, Sci. Rep. 6 (2016) 34773–34787.S. Elangovan, B.G. Nair, T.A. Small, Ceramic mixed protonic-electronic conducting membranes for hydrogen separation (2007), US 7,258,820 B2, 1997.Rosensteel, W. A., Ricote, S., & Sullivan, N. P. (2016). Hydrogen permeation through dense BaCe 0.8 Y 0.2 O 3−δ – Ce 0.8 Y 0.2 O 2−δ composite-ceramic hydrogen separation membranes. International Journal of Hydrogen Energy, 41(4), 2598-2606. doi:10.1016/j.ijhydene.2015.11.053Rebollo, E., Mortalò, C., Escolástico, S., Boldrini, S., Barison, S., Serra, J. M., & Fabrizio, M. (2015). Exceptional hydrogen permeation of all-ceramic composite robust membranes based on BaCe0.65Zr0.20Y0.15O3−δ and Y- or Gd-doped ceria. Energy & Environmental Science, 8(12), 3675-3686. doi:10.1039/c5ee01793aMontaleone, D., Mercadelli, E., Escolástico, S., Gondolini, A., Serra, J. M., & Sanson, A. (2018). All-ceramic asymmetric membranes with superior hydrogen permeation. Journal of Materials Chemistry A, 6(32), 15718-15727. doi:10.1039/c8ta04764bKim, H., Kim, B., Lee, J., Ahn, K., Kim, H.-R., Yoon, K. J., … Lee, J.-H. (2014). Microstructural adjustment of Ni–BaCe0.9Y0.1O3−δ cermet membrane for improved hydrogen permeation. Ceramics International, 40(3), 4117-4126. doi:10.1016/j.ceramint.2013.08.066(Balu) Balachandran, U., Lee, T. H., Park, C. Y., Emerson, J. E., Picciolo, J. J., & Dorris, S. E. (2014). Dense cermet membranes for hydrogen separation. Separation and Purification Technology, 121, 54-59. doi:10.1016/j.seppur.2013.10.001Shimura, T. (2001). Proton conduction in non-perovskite-type oxides at elevated temperatures. Solid State Ionics, 143(1), 117-123. doi:10.1016/s0167-2738(01)00839-6HAUGSRUD, R. (2007). Defects and transport properties in Ln6WO12 (Ln=La, Nd, Gd, Er). Solid State Ionics, 178(7-10), 555-560. doi:10.1016/j.ssi.2007.01.004Haugsrud, R., & Kjølseth, C. (2008). Effects of protons and acceptor substitution on the electrical conductivity of La6WO12. Journal of Physics and Chemistry of Solids, 69(7), 1758-1765. doi:10.1016/j.jpcs.2008.01.002Magrasó, A., Polfus, J. M., Frontera, C., Canales-Vázquez, J., Kalland, L.-E., Hervoches, C. H., … Haugsrud, R. (2012). Complete structural model for lanthanum tungstate: a chemically stable high temperature proton conductor by means of intrinsic defects. J. Mater. Chem., 22(5), 1762-1764. doi:10.1039/c2jm14981hSeeger, J., Ivanova, M. E., Meulenberg, W. A., Sebold, D., Stöver, D., Scherb, T., … Serra, J. M. (2013). Synthesis and Characterization of Nonsubstituted and Substituted Proton-Conducting La6–xWO12–y. Inorganic Chemistry, 52(18), 10375-10386. doi:10.1021/ic401104mScherb, T., Kimber, S. A. J., Stephan, C., Henry, P. F., Schumacher, G., Escolástico, S., … Banhart, J. (2016). Nanoscale order in the frustrated mixed conductor La5.6WO12−δ. Journal of Applied Crystallography, 49(3), 997-1008. doi:10.1107/s1600576716006415Van Holt, D., Forster, E., Ivanova, M. E., Meulenberg, W. A., Müller, M., Baumann, S., & Vaßen, R. (2014). Ceramic materials for H2 transport membranes applicable for gas separation under coal-gasification-related conditions. Journal of the European Ceramic Society, 34(10), 2381-2389. doi:10.1016/j.jeurceramsoc.2014.03.001Forster, E., van Holt, D., Ivanova, M. E., Baumann, S., Meulenberg, W. A., & Müller, M. (2016). Stability of ceramic materials for H2 transport membranes in gasification environment under the influence of gas contaminants. Journal of the European Ceramic Society, 36(14), 3457-3464. doi:10.1016/j.jeurceramsoc.2016.05.021Medvedev, D., Lyagaeva, J., Plaksin, S., Demin, A., & Tsiakaras, P. (2015). Sulfur and carbon tolerance of BaCeO3–BaZrO3 proton-conducting materials. Journal of Power Sources, 273, 716-723. doi:10.1016/j.jpowsour.2014.09.116Yang, L., Wang, S., Blinn, K., Liu, M., Liu, Z., Cheng, Z., & Liu, M. (2009). Enhanced Sulfur and Coking Tolerance of a Mixed Ion Conductor for SOFCs: BaZr 0.1 Ce 0.7 Y 0.2– x Yb x O 3–δ. Science, 326(5949), 126-129. doi:10.1126/science.1174811Duan, C., Kee, R. J., Zhu, H., Karakaya, C., Chen, Y., Ricote, S., … O’Hayre, R. (2018). Highly durable, coking and sulfur tolerant, fuel-flexible protonic ceramic fuel cells. Nature, 557(7704), 217-222. doi:10.1038/s41586-018-0082-6Kreuer, K. D. (2003). Proton-Conducting Oxides. Annual Review of Materials Research, 33(1), 333-359. doi:10.1146/annurev.matsci.33.022802.091825Fantin, A., Scherb, T., Seeger, J., Schumacher, G., Gerhards, U., Ivanova, M. E., … Banhart, J. (2016). Crystal structure of Re-substituted lanthanum tungstate La5.4W1−y Re y O12–δ (0 ≤ y ≤ 0.2) studied by neutron diffraction. Journal of Applied Crystallography, 49(5), 1544-1560. doi:10.1107/s1600576716011523Fantin, A., Scherb, T., Seeger, J., Schumacher, G., Gerhards, U., Ivanova, M. E., … Banhart, J. (2017). Relation between composition and vacant oxygen sites in the mixed ionic-electronic conductors La5.4W1−MO12− (M= Mo, Re; 0 ≤y≤ 0.2) and their mother compound La6−WO12− (0.4 ≤x≤ 0.8). Solid State Ionics, 306, 104-111. doi:10.1016/j.ssi.2017.04.005J.M. Serra, S. Escolástico, M.E. Ivanova, W.A. Meulenberg, H.-P. Buchkremer, D. Stöver, US2013-0216938-A1, 2013.Escolastico, S., Seeger, J., Roitsch, S., Ivanova, M., Meulenberg, W. A., & Serra, J. M. (2013). Enhanced H2Separation through Mixed Proton-Electron Conducting Membranes Based on La5.5W0.8M0.2O11.25−δ. ChemSusChem, 6(8), 1523-1532. doi:10.1002/cssc.201300091Gil, V., Gurauskis, J., Kjølseth, C., Wiik, K., & Einarsrud, M.-A. (2013). Hydrogen permeation in asymmetric La28 − xW4 + xO54 + 3x/2 membranes. International Journal of Hydrogen Energy, 38(7), 3087-3091. doi:10.1016/j.ijhydene.2012.12.105Palmqvist, L., Lindqvist, K., & Shaw, C. (2007). Porous Multilayer PZT Materials Made by Aqueous Tape Casting. Key Engineering Materials, 333, 215-218. doi:10.4028/www.scientific.net/kem.333.215Menzler, N. H., Malzbender, J., Schoderböck, P., Kauert, R., & Buchkremer, H. P. (2013). Sequential Tape Casting of Anode-Supported Solid Oxide Fuel Cells. Fuel Cells, 14(1), 96-106. doi:10.1002/fuce.201300153Schulze-Küppers, F., Baumann, S., Tietz, F., Bouwmeester, H. J. M., & Meulenberg, W. A. (2014). Towards the fabrication of La0.98−xSrxCo0.2Fe0.8O3−δ perovskite-type oxygen transport membranes. Journal of the European Ceramic Society, 34(15), 3741-3748. doi:10.1016/j.jeurceramsoc.2014.06.012Weirich, M., Gurauskis, J., Gil, V., Wiik, K., & Einarsrud, M.-A. (2012). Preparation of lanthanum tungstate membranes by tape casting technique. 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Functional properties of La0.99X0.01Nb0.99Al0.01O4−δ and La0.99X0.01Nb0.99Ti0.01O4−δ proton conductors where X is an alkaline earth cation. Journal of the European Ceramic Society, 35(4), 1239-1253. doi:10.1016/j.jeurceramsoc.2014.11.009Dittmeyer, R., Boeltken, T., Piermartini, P., Selinsek, M., Loewert, M., Dallmann, F., … Pfeifer, P. (2017). Micro and micro membrane reactors for advanced applications in chemical energy conversion. Current Opinion in Chemical Engineering, 17, 108-125. doi:10.1016/j.coche.2017.08.001Mauer, G., Vaßen, R., & Stöver, D. (2009). Thin and Dense Ceramic Coatings by Plasma Spraying at Very Low Pressure. Journal of Thermal Spray Technology, 19(1-2), 495-501. doi:10.1007/s11666-009-9416-0Bakan, E., & Vaßen, R. (2017). Ceramic Top Coats of Plasma-Sprayed Thermal Barrier Coatings: Materials, Processes, and Properties. Journal of Thermal Spray Technology, 26(6), 992-1010. doi:10.1007/s11666-017-0597-7Jarligo, M. O., Mauer, G., Bram, M., Baumann, S., & Vaßen, R. 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The environmental security debate and its significance for climate change

Policymakers, military strategists and academics all increasingly hail climate change as a security issue. This article revisits the (comparatively) long-standing “environmental security debate” and asks what lessons that earlier debate holds for the push towards making climate change a security issue. Two important claims are made. First, the emerging climate security debate is in many ways a re-run of the earlier dispute. It features many of the same proponents and many of the same disagreements. These disagreements concern, amongst other things, the nature of the threat, the referent object of security and the appropriate policy responses. Second, given its many different interpretations, from an environmentalist perspective, securitisation of the climate is not necessarily a positive development

Restricting digital sites of dissent: commercial social media and free expression

The widespread use of commercial social media platforms by protesters and activists has enhanced protest mobilisation and reporting but it has placed social media providers in the intermediary role as facilitators of dissent and has thereby created new challenges. Companies like Google and Facebook are increasingly restricting content that is published on or distributed through their platforms; they have been subject to obstruction by governments; and their services have been at the core of large-scale data collection and surveillance. This article analyses and categorises forms of infrastructure-based restrictions on free expression and dissent. It shows how private intermediaries have been incorporated into state-led content policies; how they set their own standards for legitimate online communication and intervene accordingly; and how state-based actions and commercial self-regulation intersect in the specific area of online surveillance. Based on a broad review of cases, it situates the role of social media in the wider trend of the privatisation of communications policy and the complex interplay between state-based regulation and commercial rule-making

Phosphodiesterase-5 inhibitors have distinct effects on the hemodynamics of the liver

<p>Abstract</p> <p>Background</p> <p>The NO - cGMP system plays a key role in the regulation of sinusoidal tonus and liver blood flow with phosphodiesterase-5 (PDE-5) terminating the dilatory action of cGMP. We, therefore, investigated the effects of PDE-5 inhibitors on hepatic and systemic hemodynamics in rats.</p> <p>Methods</p> <p>Hemodynamic parameters were monitored for 60 min. after intravenous injection of sildenafil and vardenafil [1, 10 and 100 μg/kg (sil1, sil10, sil100, var1, var10, var100)] in anesthetized rats.</p> <p>Results</p> <p>Cardiac output and heart rate remained constant. After a short dip, mean arterial blood pressure again increased. Systemic vascular resistance transiently decreased slightly. Changes in hepatic hemodynamic parameters started after few minutes and continued for at least 60 min. Portal (var10 -31%, sil10 -34%) and hepatic arterial resistance (var10 -30%, sil10 -32%) decreased significantly (p < 0.05). At the same time portal venous (var10 +29%, sil10 +24%), hepatic arterial (var10 +34%, sil10 +48%), and hepatic parenchymal blood flow (var10 +15%, sil10 +15%) increased significantly (p < 0.05). The fractional liver blood flow (total liver flow/cardiac output) increased significantly (var10 26%, sil10 23%). Portal pressure remained constant or tended to decrease. 10 μg/kg was the most effective dose for both PDE-5 inhibitors.</p> <p>Conclusion</p> <p>Low doses of phosphodiesterase-5 inhibitors have distinct effects on hepatic hemodynamic parameters. Their therapeutic use in portal hypertension should therefore be evaluated.</p

The Digitalization of Russian Politics and Political Participation

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