Neste trabalho foi realizado um estudo para verificar as melhores condições de vazão das atuais lanças supersônicas utilizadas no forno elétrico a arco 3 da Siderúrgica Riograndense. Também foi realizado um teste comparativo entre o modelo de lança supersônica atual e um novo modelo de injetor proposto. Para determinar as melhores condições de vazão das injetoras atuais, avaliou-se parâmetros como o consumo de oxigênio, energia elétrica, teor de FeO da escória, condições de desgaste do refratário e erosão dos bicos injetores. Para os testes comparativos com o novo modelo de injetores, foram usinados dois bicos de cobre com menor diâmetro de garganta. As novas pressões e vazões de oxigênio, tanto para o trabalho no modo alta vazão como para o modo purga, foram estabelecidas com base em estudos das características dos bicos utilizados atualmente. Os testes foram realizados em caráter comparativo no próprio forno 3. Nos atuais modelos de injetores utilizados, verificou-se que a pressão no modo purga deve variar entre 0,9 e 1,1 kgf/cm2 na rede de oxigênio. Assim, a vazão de O2 varia entre 65 e 75 Nm3/h, intervalo no qual foi observada a melhor eficiência na operação, considerando principalmente o controle do FeO da escória e a ocorrência de entupimento dos bicos supersônicos. Na alta vazão foram definidas pressões entre 9,0 e 9,5 kgf/cm2, onde as vazões variam entre 350 e 375 Nm3/h por bico. Estes valores foram definidos avaliando-se principalmente o controle do consumo de refratário na região do injetor e o desgaste dos bicos causado por jato subacelerado. Os injetores com diâmetro de garganta menor possibilitaram a operação com vazões de O2 menores na purga em relação ao modelo atual. Assim, foi possível operar com vazão em torno de 50 Nm3/h a uma pressão de 0,9 kgf/cm2, sem a ocorrência de entupimentos. Porém no modo alta vazão, para garantir a vazão mínima de 350 Nm3/h, a pressão no bico foi elevada para 12,5 kgf/cm2. Com este novo modelo de injetor, os consumos médios de oxigênio e de energia elétrica reduziram 0,8 Nm3/t e 12,9 kWh/t, respectivamente, em relação ao injetor atual, e verificou-se o aumento de 0,92% no rendimento metálico. / In this work, a study to verify the best conditions of oxygen flow to operate the supersonic injectors currently used in the Electric Arc Furnace 3 (EAF 3) of Siderúrgica Riograndense was carried out. Also, a comparative study between the supersonic injector model currently used and a new proposed model was made. To determine the best flow conditions of current injectors, parameters such as oxygen and electricity consumption, and slag FeO content were evaluated. Moreover, refractory wear conditions and copper lance tips erosion were analyzed. For the comparative tests with the new model, two copper lance tips have been machined, with a smaller throat diameter. The new oxygen pressure and oxygen flow (high and low flow operating modes) were established based on studies of features of the currently used lance tips. The tests were carried out comparatively in the same EAF 3. For the currently used injector models, it was verified that the pressure in the low flow mode must be kept between 0.9 and 1.1kgf/cm2 in the oxygen system. Thus, the O2 flow varies between 65 and 75 Nm3/h, interval in which the best efficiency in the operation was observed, considering mainly the control of FeO of the slag, and the occurrence of clogging of the supersonic lance tips. High flow pressures were defined between 9.0 and 9.5 kgf/cm2, where the flow varies between 350 and 375 Nm3/h per lance tip. These values were defined evaluating mainly the control of the refractory wear in the region of the injector, and the erosion of the lance tips caused by under-blown jet. The new lance tips with smaller throat diameter made it possible to operate with smaller O2 flow, 50 Nm3/h with pressure of 0.9 kgf/cm2, without clogging in low flow steps. However, in the high flow, to guarantee the minimum flow of 350 Nm3/h, the pressure in the lance tips was raised to 12.5 kgf/cm2. With this new model of injector, the average consumption of oxygen was lowered by 0.8 Nm3/h compared to the current injector and an increase of 0.92% was verified in the metallic yield. Furthermore, there was a reduction of 12.9 kWh/t in the consumption of electric energy.

This interactive session will provide participants with examples and demonstrations of ten excellent (and highly adaptable) literacy strategies. These are doable, effective, and highly engaging.

This study produced and analyzed shaped tungsten wire tips formed through electrochemical etching. Specifically, the cone length and the radius of curvature of the tip were analyzed. Having the tips move dynamically through an electrolytic solution, such as potassium hydroxide, and tuning the initial starting depth of the tungsten wire along with the dynamic speed of the tungsten wire as it passed throughout the solution allowed various types of tip profiles to be produced. The tip's radius of curvature was able to be reproduced with an accuracy between 88 - 92 %. The method provided would be applicable for the production of various styles of liquid-metal ion source (LMIS) probes and scanning probe microscope (SPM) tips.

Background: It has been reported that transjugular intrahepatic portosystemic shunting (TIPS) might be utilized as a salvage option for hepatorenal syndrome (HRS), while randomized controlled trials are pending and real-world contemporary data on inpatient mortality is lacking. Methods: We conducted an observational retrospective cohort study from the National Inpatient Sample from 2005 to 2014. We included all adult patients admitted with HRS and cirrhosis, using ICD 9-CM codes. We excluded cases with variceal bleeding, Budd–Chiari, end-stage renal disease, liver transplant and transfers to acute-care facilities. TIPS’ association with inpatient mortality was assessed using multivariable mixed-effects logistic regression, as well as exact-matching, thus mitigating for TIPS selection bias. The exact-matched analysis was repeated among TIPS-only versus dialysis-only patients. Results: A total of 79,354 patients were included. Nine hundred eighteen (1.2%) underwent TIPS. Between TIPS and non-TIPS groups, mean age (58 years) and gender (65% males) were similar. Overall mortality was 18% in TIPS and 48% in dialysis-only cases (n = 10,379; 13.1%). Ninety six (10.5%) TIPS patients underwent dialysis. In-hospital mortality in TIPS patients was twice less likely than in non-TIPS patients (adjusted odds ratio [aOR] = 0.43, 95% CI 0.30–0.62; p < 0.001), with similar results in matched analysis [exact-matched (em) OR = 0.39, 95% CI 0.17–0.89; p < 0.024; groups = 96; unweighted n = 463]. Head-to-head comparison showed that TIPS-only patients were 3.3 times less likely to succumb inpatient versus dialysis-only patients (contrast aOR = 0.31, 95% CI 0.20–0.46; p < 0.001), with similar findings post-matching (emOR = 0.22, 95% CI 0.15–0.33; p < 0.001; groups = 54, unweighted n = 1457). Conclusions: Contemporary, real-world data reveal that TIPS on its own, and when compared to dialysis, is associated with decreased inpatient mortality when utilized in non-bleeders-HRS patients. Further randomized studies are needed to establish the long-term benefit of TIPS in these patients.

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The battery separator is a component of the conventional battery that for long has been overlooked. Just because it’s the only inactive component, doesn’t mean it’s any less important for the battery cell. Recent trends point to an immense growth of the electrical vehicle-industry, and by so, also the lithium-ion battery separators market. This is because the lithium-ion battery is the most common battery type in commercial electrical vehicles. In one of the major manufacturing processes of the separator, mineral oil is used, to achieve a porous film. This study aims to evaluate different oils interaction with the polymer resin in the manufacturing process. Since most oils used in the battery separator industry today use paraffin rich oils, oils with different naphthenic content is tested to find correlations between the oils properties and the crystallinity or the porosity. No correlations for either the porosity or the crystallinity could be made to the oil’s properties. The images taken with the SEM was not enhanced enough to study the pores themselves or the pore structure of the films. For future studies it is recommended to collect more data to identify outliers so more accurate values are obtained. The methodology needs to be verified to ensure the procedure is reproducible. For the study of the pores and the pore structure, an FE-SEM should be used to achieve greater quality enhancement images on the surface of the films. / Batteri separatorn är en komponent i det konventionella batteriet som länge har förbisetts. Bara för att den är en inaktiv komponent, betyder inte att den är mindre viktig för battericellens prestation. Trender idag pekar mot en enorm tillväxt inom elbils-industrin, och med det även litium-jon batteriseparatorns marknad. Det är för att litium-jon batteriet är det batteriet som vanligen används kommersiellt idag i elbilar. I en av de två stora industriella tillverkningsprocesserna används olja för att åstadkomma en porös film. Denna studie syftar på att utvärdera olika oljors interaktion med polymeren i denna tillverkningsprocess. Eftersom de flesta batteriseparator-industrier idag använder paraffinrik olja så testas oljor med olika mycket naftalensikt innehåll för att hitta korrelationer mellan oljornas egenskaper och kristalliniteten eller porositeten hos filmerna. Inga korrelationer för porositeten eller kristalliniteten kunde göras till oljornas egenskaper. Bilderna tagna med SEM var ej tillräckligt förstorade för att kunna studera vare sig porstorleken eller porstrukturen hos filmerna. För framtida studier rekommenderas att samla in mer data för att kunna utskilja ”outliers” i datan, för att erhålla mer korrekta värden. Metodiken måste även verifieras för att säkerställa att proceduren är reproducerbar. För att studera porerna och porstrukturen, borde en FE-SEM användas för att få mer förstorade bilder med bättre kvalité på filmernas yta.

Flow state is a state of intense focus and engagement, which is fulfilling for people experiencing it and therefore generally sought-after by creators of virtual games and experiences. Virtual Reality (VR) is known to be one of the most immersive technologies available today. As such, it has great potential to foster flow state in its users. This work tries to determine which design characteristics favor flow the most, with regard to providing guidance to the user. In particular, this research examines whether in a VR escape room, text hints or glowing cues are more effective to foster feelings of flow. The research process included design and implementation of the VR escape room from the ground up, to create the perfect setting for the experiments, a VR experience in which ultimate goal and intermediate steps are precisely defined. This allows to give relevant hints every step of the experience, and to examine the effects of hints design on flow. The intensity of the resulting flow state has been evaluated through the Activity Flow State Scale (AFSS) designed by Payne et al., and qualitative data has also been gathered, from direct observation and user comments. AFSS score, duration of the VR experience, and duration estimated by the users, have been compared between the version of the VR escape room which presents hints as text prompts and the one in which relevant objects glow. This data has then been connected to findings resulting from the thematic analysis of direct observation and user comments. Lastly, general insights and guidelines have been extracted, to inform designers and game developers willing to create flow-oriented VR experiences. / “Flow state” är ett tillstånd av intensivt fokus och engagemang, vilket är tillfredsställande för dem som upplever det och är därför eftertraktat av skapare av virtuella spel och upplevelser. Virtual Reality (VR) är känd som en av de mest immersiva tekniker som finns tillgänglig idag. Som sådan har den stor potential att främja “flow state” hos sina användare. Detta arbetet försöker fastställa vilka designegenskaper som gynnar “flow” mest, när det gäller att ge vägledning till användaren i en VR-upplevelse. Arbetet undersöker om det i ett VR-”escape room” är effektivare att ge användaren tips i text eller som lysande signaler för att främja känslan av flow. Forskningsprocessen omfattade utformning och implementation av ett VR-”escape room” från grunden för att skapa den perfekta miljön för experimenten, en VR-upplevelse där slutmålet och de mellanliggande stegen är exakt definierade. Detta gör det möjligt att ge relevanta tips i varje steg av upplevelsen och att undersöka effekterna av tipsens utformning på flödet. Intensiteten i ett resulterande “flow state”har utvärderats med hjälp av Activity Flow State Scale (AFSS) som utformats av Payne m.fl. och kvalitativa data har också samlats in från direkta observationer och användarkommentarer. AFSS-poäng, VR-upplevelsens varaktighet och användarnas uppskattade varaktighet har jämförts mellan två versioner av ett VR-”escape room”. Ett där tips presenteras som textmeddelanden och ett där relevanta objekt lyser. Datan har sedan kopplats samman med resultaten från den tematiska analysen av direkta observationer och användarkommentarer. Slutligen har allmänna insikter och riktlinjer tagits fram för att informera designers och spelutvecklare som vill skapa “flow state”-orienterade VR-upplevelser.

Over the past several decades, the victimization of women on college campuses has not decreased despite an uptick in research and concern surrounding the topic. In this study, I analyzed the victimization prevention messages on the websites of 30 4-year PWIs and 30 4-year HBCUs in the Southeastern United States to investigate how they contextualized such messages. Drawing on a comparative thematic analysis of 132 documents from HBCUs and 138 documents from PWIs, I elaborate on four key themes, with several subthemes: gendered safety messages, rape culture education, racialized safety messages, and collective responsibility. I found that victimization prevention messaging was contextualized by community engagement at HBCUs, and both types of schools engage in victim-centered crime prevention. Additionally, PWIs used language on their webpages that encourages peer-to-peer racialized coveillance. This study contributes to the literature on victimization prevention on college campus, the college-prison nexus, and understandings of sexual assault prevention.

Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / Land is typically the highest value category of assets that farmers and ranchers have on their balance sheets. The value of land is affected by inflation. Understanding the effect of inflation on the land market helps farmers make better land pricing decisions and better asset management decisions. Using Treasury Bills and Farm Credit Bonds, future inflation expectations and agricultural risk premiums can be estimated. With the recent government stimulation of the economy and the resulting large amount of money infused into the economy, inflation is becoming an increasing concern with investors. Economic theory suggests that this infusion of money will affect future interest rates and ultimately the value of land given the inverse relationship between interest rates and the value of land. These lingering affects occur with the rise and fall of yield rates for Treasury Bills and Farm Credit bonds. Farm Credit bonds are sold at a premium over Treasury Bills. This premium indicates the market-assessed additional risk that farmers have to pay for their operating loans and other mortgages. Even though land values are affected by inflation, other things affect land values such as recreational use, development, and natural resource exploration. A combination of inflation and these other affects can greatly affect land prices.