Five manhole models, three composed of brick and two composed of concrete, were created in the laboratory with the goal of simulating existing manholes in the field that have been deteriorated by stress and corrosion. The samples were rehabilitated using three different liners: a plastic polyurea spray-on liner applied to a brick manhole, an HDPE slip liner (grouted in place) applied to a brick and concrete specimen, and a calcium aluminate grout applied to a brick and concrete specimen. Each sample was tested under axisymmetric pressure in the hoop compression cell, simulating horizontal effective stresses that act on a manhole in a radially symmetric manner. At 500 kPa, minimal radial deflections were observed with no notable damage to any specimen. Each specimen was then tested in a diametrically opposed 2-point loading setup to test the manhole in bending which may be induced to on a structure in the field by surface activity or adjacent excavation. The sample rehabilitated with the plastic spray-on liner behaved in a ductile manner, yielding at the lowest strength. The samples rehabilitated with the calcium aluminate grout exhibited high peak strengths, but yielded in catastrophic failure at small deformations. The samples repaired with the HDPE slip liner also produced high peak strengths with the grout component yielding in brittle failure, but residual strengths mobilized in the HDPE liner prevented total collapse of the samples. Although all of the liners tested present viable rehabilitation solutions within the prescribed deformation limits, the HDPE slip liner is the preferred method of treatment solely based on considerations of strength and ductility; practical considerations of cost and constructability also need consideration. / Thesis (Master, Civil Engineering) -- Queen's University, 2007-09-21 12:14:38.983

What if the means to capture and store carbon dioxide (CDR) would be researched,  developed, and deployed under an ethos of care, rather than in the tech-deterministic,  market-fixated way it is currently done and  how can  people in Northern Scandinavia lead  this process in their region and benefit from it as a community while doing regenerative  work for the benefit of the global biosphere?

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-27T11:30:41Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-03-27T13:52:08Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2018-03-27T13:52:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-06-30 / Florações de cianobactérias são consequência principalmente da eutrofização de ambientes aquáticos que afeta a qualidade e compromete o uso da água para diversas finalidades. A restauração de sistemas aquáticos eutrofizados é um dos principais desafios da limnologia atual. Nosso objetivo foi identificar as principais causas do processo de eutrofização e ocorrência de florações de cianobactérias e testar a eficácia e aplicabilidade do uso combinado de coagulantes e adsorventes de P em fase sólida no controle da eutrofização e florações em um lago tropical raso. O estudo foi conduzido no lago do Museu Mariano Procópio, localizado em Juiz de Fora – MG e dividido em quatro fases. As duas primeiras fases compreendem uma análise sistêmica do lago. Na primeira, buscou-se conhecer a dinâmica da comunidade fitoplanctônica a fim de entender a dominância de cianobactéria deste sistema. Na segunda, foram avaliados os aportes de fósforo (P) para o sistema. Na terceira fase foram realizados experimentos em laboratório, para verificar a eficácia de diferentes coagulantes e lastros para remoção de cianobactérias. E na quarta fase foram realizados experimentos em mesocosmos no lago, para testar o controle da eutrofização e florações de cianobactérias. A análise sistêmica mostrou dominância de diferentes espécies de cianobactérias e que as altas concentrações de nutrientes presentes do sistema vêm principalmente de contribuição externa. O uso combinado de coagulantes e lastros foi eficiente para a remoção de biomassa de cianobactérias, porém foi dependente da espécie. Nos experimentos com mesocosmos, foi observada uma forte redução de Clorofila a (Chl a 85%) e fósforo total (TP 78%) (p <0,0010) em todos os tratamentos, porém estas reduções não se mantiveram ao longo do tempo. Para mitigar as florações de cianobactérias deste sistema, será necessário o controle das fontes externas de nutrientes e um ajuste na técnica de coagulante-lastro para manter a clorofila e o fósforo total em concentrações reduzidas por mais tempo. / Cyanobacterial Blooms are mainly a consequence of eutrophication of aquatic environments that affect the water quality and compromise the use of water for various purposes. The restoration of eutrophic aquatic systems is one of the main challenges of today's limnology. Our objective was to identify the main causes of the eutrophication process and the occurrence of cyanobacterial blooms in a shallow tropical lake, and to test the efficacy and applicability of the combined use of coagulants and adsorbents of P in solid phase for the control of eutrophication and cyanobacteria blooms in a tropical shallow system. The study was conducted in the lake of the Mariano Procópio Museum, located in Juiz de Fora - MG and divided into four phases. The first two phases comprised a systemic analysis of the lake. The first one sought to know the dynamics of the phytoplankton community and to understand the causes of the cyanobacteria dominance in this system. In the second one, the main contributions of phosphorus to the system and the general balance of P were evaluated. In the third phase, laboratory experiments were carried out to evaluate the efficacy of different coagulants and ballasts for the removal of cyanobacteria. Last, in the fourth phase experiments were carried out in mesocosmos in the lake to test the control of eutrophication and cyanobacterial blooms. The systemic analysis showed the dominance of different species of cyanobacteria and that the high concentrations of nutrients present in the system come mainly from external contribution. The combined use of coagulants and ballasts was efficient for the removal of cyanobacteria biomass, but it is dependent on the species pool. In the experiments with mesocosms, a strong reductions of chloropyll a (Chl a) 85% and total phosphorus (TP) 78% (p < 0.001) were observed in all treatments, however these reductions were not lasting. To mitigate the cyanobacterial blooms of this system, it will be necessary to control the external sources of nutrients and also an adjustment in the coagulant-ballast technique to keep Chl a l and TP in reduced concentrations for longer time.

Östersjön är idag det system med störst utbredning av syrefattiga eller syrefria bottnar i hela världen. Problemet har uppstått som följd av den massiva näringsbelastning från de kringliggande länderna som pågått sedan industrialiseringen intensifierades på 1900-talet. I och med omställningen till förnybar energi planeras framtida vindkraftsparker att byggas i Östersjön. Överflödig energi planeras att användas till havsbaserad vätgasproduktion som sedan forslas in till land med rör. Vid storskalig vätgasproduktion produceras som biprodukt enorma mängder syrgas vilket ger helt nya förutsättningar för artificiell syresättning av Östersjöns syrefria bottnar. Tre övergripande tekniker för att artificiellt syresätta bottenvatten med syrgas har identifierats på 21 platser runt om i världen: Downflow Bubble Contact System (DBCS), Side Stream Pumping System (SSPS) och Direct Oxygen Injection System (DOIS). Alla tre tekniker har med goda resultat förhöjt syrgaskoncentrationen i bottenvatten från hypoxiskt (&lt; 2 mg/l) till oxiskt (&gt; 2 mg/l). I flera fall har syresättningen bidragit till reduktion av näringsämnen och/eller utökat habitat för fiskar och bottendjur. En pilotanläggning i fjärden Slätbaken skulle ge bättre förståelse för hur ett system skulle kunna utformas i andra delar av Östersjön. En massbalansmodell konstruerades över Slätbaken och resultatet var att pilotanläggningen bör ha en kapacitet på 8 ton O2/dygn för att med säkerhet kunna höja syrgaskoncentrationen till &gt; 4 mg/l. Detta skulle ge en lämplig säkerhetsmarginal för den lokala bottennära eller bottenlevande faunan med avseende på syrgashalt. / As of today, the Baltic Sea is the system with the globally largest expansion of hypoxic or anoxic bottom waters, so-called “dead zones”. It is a consequence of the massive load of nutrients from the surrounding countries that started with the intensified industrialization in the start of the 20th century. With the transformation towards renewable energy, wind parks are planned to be built in the Baltic Sea on a substantial scale. Thereby, superfluous energy is planned to be used for sea-based production of hydrogen gas that can be piped to land. Large scale hydrogen gas production would generate enormous amounts of oxygen gas as a byproduct, which gives a theoretical opportunity to artificially oxygenate the dead zones of the Baltic Sea. Three main techniques to artificially oxygenate bottom waters were identified in 21 freshwater systems around the world: Downflow Bubble Contact System (DBCS), Side Stream Pumping System (SSPS) and Direct Oxygen Injection System (DOIS). All three techniques have successfully raised the concentration of dissolved oxygen from hypoxic (&lt; 2 mg/l) to oxic (&gt; 2 mg/l). In many cases, the oxygenation contributed to reduction of dissolved nutrients in the waters and/or enlarged habitats for fish and benthic fauna. A pilot plant for oxygenation in the bay Slätbaken would contribute to better understanding of how a future oxygenation system could be constructed in other parts of the Baltic Sea. A mass balance model was constructed, representing oxygen content and transport in Slätbaken. Results indicated that establishing a pilot plant would need a capacity of 8 tons O2/day to guarantee a dissolved oxygen concentration of &gt; 4 mg/l, which would provide local fauna with a suitable safety margin regarding dissolved oxygen concentrations.

Satire erlaubt alles – so die Aussage einiger Comedians und Freunde des gepflegten Spöttelns. Doch wenn politisches Kabarett dazu beiträgt, Falschinformationen und Fehlinterpretationen zu verbreiten – darf Satire dann immer noch alles? Trägt nicht auch das politische Kabarett Verantwortung für eine adäquate Faktendarstellung anstelle einseitiger Politisierung? Satire blendet leider auch einige Fakten und Wirkbezüge in der Klimadebatte und den wissenschaftlichen Erkenntnissen aus. Dass diese Blindheit und Ignoranz nicht zwingend zuträglich für eine gesellschaftliche Entwicklung und die Aufgeklärtheit einer Gesellschaft sind, liegt auf der Hand – aller Freiheit politischer Satire zum Trotz. Auch wenn zu viel Informationen und Wissen, und erst recht ambigue und widersprüchliche Daten, zu Verwirrungen und häufig nicht zur Irritation der eigenen (festgefahrenen) Weltbilder führen können, soll dieser Beitrag die Vielfalt der Daten und Interpretationsspielräume aufzeigen und zu mehr factfulness in der Klimadiskussion motivieren. / Satire allows everything - so the statement of some comedians and friends of the cultivated mockery. But if political cabaret contributes to spreading misinformation and misinterpretations - is satire still allowed to do everything? Doesn't political cabaret also bear responsibility for an adequate presentation of facts instead of one-sided politicization? Unfortunately, satire also ignores some facts and causal relations in the climate debate and scientific knowledge. It is obvious that this blindness and ignorance is not necessarily conducive to social development and the enlightenment of a society - despite all the freedom of political satire. Even if too much information and knowledge, and even more so ambiguous and contradictory data, can lead to confusion and often not to the irritation of one's own (deadlocked) world views, this contribution is intended to show the diversity of data and scope for interpretation and motivate more factfulness in the climate debate.