Currently, four areas of Texas have been designated by the United States Environmental Protection Agency (EPA) as non-attainment areas because they exceeded the national one-hour ground-level ozone standard of 0.12 parts-per-million (ppm). Ozone is formed in the atmosphere by the reaction of Volatile Organic Compounds (VOCs) and Nitrogen Oxides (NOx) in the presence of heat and sunlight. In May 2002, The Texas State Legislature passed Senate Bill 5, the Texas Emissions Reduction Plan (TERP), to reduce the emissions of NOx by several sources. As part of the 2001 building energy performance standards program which is one of the programs in the TERP, the Texas Legislature established the 2000 International Energy Conservation Code (IECC) as the state energy code. Since September 1, 2001, the 2000 IECC has been required for newly constructed single and multifamily houses in Texas. Therefore, this study develops and applies portions of a methodology to calculate the energy savings and NOx emissions reductions from the adoption of the 2000 IECC to new single family houses in non-attainment and affected counties in Texas. To accomplish the objectives of the research, six major tasks were developed: 1) baseline data collection, 2) development of the 2000 IECC standard building simulation, 3) projection of the number of building permits in 2002, 4) comparison of energy simulations, 5) validation and, 6) NOx emissions reduction calculations. To begin, the 1999 standard residential building characteristics which are the baseline construction data were collected, and the 2000 IECC standard building characteristics were reviewed. Next, the annual and peak-day energy savings were calculated using the DOE-2 building energy simulation program. The building characteristics and the energy savings were then crosschecked using the data from previous studies, a site visit survey, and utility billing analysis. In this thesis, several case study houses are used to demonstrate the validation procedure. Finally, the calculated electricity savings (MWh/yr) were then converted into the NOx emissions reductions (tons/yr) using the EPA's eGRID database. The results of the peak-day electricity savings and NOx emissions reductions using this procedure are approximately twice the average day electricity savings and NOx emissions reductions.

This thesis pertains to development of preliminary combustor design tools for prediction of NOx emissions from aircraft gas turbine combustors. These tools are developed in the form of chemical reactor models and their objective is to predict the formation of NOx based on combustor geometry and engine input parameters such as inlet pressure, inlet temperature, fuel flow and air flow. The construction of the reactor networks follow from cold flow computational fluid dynamics results as it provides a way for allocating volumes to each reactor in the network. The ability of the model to predict NOx has been analysed by comparing predictions with measured data and theoretical trends. The model predictions for different combustors satisfy theoretical trends across various thrust levels in that the model correctly captures the effect of various input parameters on NOx formation and predicts most power conditions for various combustors within 15% of the measured value.

This thesis pertains to development of preliminary combustor design tools for prediction of NOx emissions from aircraft gas turbine combustors. These tools are developed in the form of chemical reactor models and their objective is to predict the formation of NOx based on combustor geometry and engine input parameters such as inlet pressure, inlet temperature, fuel flow and air flow. The construction of the reactor networks follow from cold flow computational fluid dynamics results as it provides a way for allocating volumes to each reactor in the network. The ability of the model to predict NOx has been analysed by comparing predictions with measured data and theoretical trends. The model predictions for different combustors satisfy theoretical trends across various thrust levels in that the model correctly captures the effect of various input parameters on NOx formation and predicts most power conditions for various combustors within 15% of the measured value.

Atherosclerosis is a complex inflammation condition involving the accumulation of lipid-filled macrophages within the artery wall. Progression of the initial fatty streak to an advanced atherosclerotic plaque is characterized by the development of a necrotic core region containing cholesterol and dead cells. The oxidation of low-density lipoprotein (LDL) to oxidized LDL (oxLDL) and its subsequent uptake by macrophages to form foam cells are the key process in plaque formation. OxLDL is found within atherosclerotic plaque, and it is cytotoxic to a range of cells including macrophages through the generation of reactive oxygen species (ROS) and induction of oxidative stress. The aim of this study was to examine the cytotoxic effects of oxLDL to U937 human monocyte-like cells. OxLDL caused a rapid concentration-dependent cell viability loss in U937 cells within 6 hours. The progression of oxLDL-induced cell death was found to be strongly correlated with the intracellular ROS production and intracellular glutathione (GSH) loss. OxLDL also caused a rapid loss of intracellular aconitase activity, indicating the impairment of the cellular metabolic function. The cytosolic calcium ion (Ca²⁺) level was also elevated by oxLDL, which could be from both intra- and extra-cellular sources. OxLDL also activated plasma membrane superoxide generation complex NADPH oxidase (NOX), and the progression of oxLDL-induced NOX activation was correlated with oxLDL-mediated ROS production, suggesting NOX is the major source of ROS. Further investigations using NOX inhibitors apocynin or diphenyleneiodonium (DPI) found that inhibition of NOX prevented oxLDL-induced cell viability loss, ROS production, GSH loss and aconitase activity decrease. The cytosolic Ca²⁺ elevation caused by oxLDL was also suppressed slightly by inhibiting NOX activity. These results clearly show that NOX is the major site of oxidative stress upon oxLDL activation, contributing to the oxLDL-induced cell death. This study also examined the protective effect of 7,8-dihydroneopterin (7,8-NP) on oxLDL-induced oxidative stress. 7,8-NP dramatically protected cells from oxLDL-induced cell viability loss, ROS generation and aconitase activity loss. 7,8-NP also inhibited oxLDL-induced cytosolic Ca²⁺ influx particularly after 3 hours. 7,8-NP did not inhibited mitochondrial aconitase activity decrease caused by oxLDL, nor inhibited mitochondrial ROS production. This indicates the protective effect of 7,8-NP against oxLDL damage could primarily in cytoplasm. The failure of 7,8-NP protection from oxLDL activating NOX suggests that the protection of 7,8-NP against oxLDL-induced oxidative stress was not due to the inhibition of NOX activation, but by radical scavenging activity of the NOX products.

No description available.

Diesel scandal news (Dieselgate) in which Volkswagen fitted defeat devices on cars equipped with the EA 189-engine have appeared in media since September 2015. Sales of affected cars worldwide has led to globally seen consequences. Resulting in prosecutions and bad publicity, highlighting how Volkswagen have deceived their customers. In this thesis I have investigated what effects this scandal has had on Swedish customer’s perception of Volkswagen as a brand. My research method has consisted of different parts. I have received answers from structural questions to journalists, comments from owners and potential buyers online, interviewed customers and also had a dialogue with Volkswagen. I have found that most customer lack trust for Volkswagen as a brand, but their perception of Volkswagens products are generally good. They have throughout the ongoing scandal focused on delivering quality products. This having been the success formula that helped Volkswagen put a shade on “Dieselgate” and focus on the future. “Dieselgate” shows us that trust is not necessarily required to be able to increase sales.

Vasa värme är ett företag som producerar och levererar fjärrvärme. Anläggningen i Kalixomfattar bland annat en 10 MW rosterpanna, FBP2, som eldas med fuktigt biobränsleoch Vasa värme vill sänka sina NOx-emissioner från denna panna. Syftet och målet meddetta examensarbete är att förstår hur förbränning leder till NOx-bilning i FBP2 och geförslag på hur emissionerna kan minskas. Arbetet studerar hur termisk-, bränsle- och prompt NOx bildas samt utvärderar reducerandeåtgärder. Primära åtgärder i form av flerstegsförbränning, rökgasåterföring, reburningoch bäddformation har studerats tillsammans med de sekundära åtgärderna SCR och SNCR. För att kunna utvärdera hur väl de olika åtgärderna skulle fungera för FBP2 har mätdatasamlats in och en CFD modell skapats utifrån ett verklig driftfall. Modellens temperaturprofiljämförs med fyra termoelement som finns utplacerade i FBP2 och i tre av fyrafall överensstämmer temperaturmätningarna med det modellen visar. I det fjärde fallet ärdet något osäkert om termoelementet ger ett korrekt resultat. Temperaturprofilen visaratt det finns områden som skulle gynna en reduktionsreaktion för SNCR men modelleninnehåller förenklingar i detta områden vilket innebär att den verkliga temperaturen ärlägre än det modellen visar. De simulerade NOx värdena överensstämmer med de somuppmätts och modellen visar att det bara bildas bränsle NOx. Fyra fall med ändrar geometri simuleras; ett med fler tertiärlufthål, ett utan tertiärlufthål,ett med fler sekundärlufthål och ett med halverad primärluft. Alla fall utom halveradprimärluft, som visade på en rejäl NOx sänkning, gav högre simulerade NOx värden. I fortsättningen föreslås att det NOx-reducerande arbetet ska innefatta att minska primärluftmängdenoch undersöka möjligheten att installera SNCR. Modellen kan användasför fortsatt arbete men innan dess bör modellens geometri utökas, en del förenklingar börarbetas bort och modellen

Globalt sett används fossila bränslen fortfarande till största delen, och industrisektorn är den med störst energianvändning. Därför är det viktigt att fortsätta arbetet med att hitta nya sätt att använda befintliga resurser, att utveckla energibesparande tekniker och att göra detta med hållbarhetsperspektivet i fokus. Denna studie är förlagd på kraftvärmeverket i Sandviken, som producerar fjärrvärme och elektricitet. Anläggningen ägs av Sandviken Energi AB som är ett kommunalt energibolag med ansvar för infrastrukturen i Sandvikens kommun. Syftet med studien är att undersöka möjligheten att sänka halten av kväveoxider, NOx, som släpps ut med rökgaserna, samt att rena det kondensat som bildas när rökgaserna värmeväxlas. Det finns en stor vinning i att minska NOx-utsläppen ur ett miljöperspektiv, eftersom de orsakar försurning och andra problem i naturen. Tillvägagångssättet är att dosera extra ammoniak vid förbränningen. Vid höga temperaturer reagerar ammoniak med kväveoxiderna och utsläppen av dessa minskar. 90 % av ammoniakutsläppen kan sedan återvinnas med en ammoniakstripper för att även dessa ska hållas inom gränsvärdena. Möjligheten att använda det vatten som bildas då rökgaserna kondenserar undersöks också. Många anläggningar skulle teoretiskt sett kunna bli helt självförsörjande i sin vattenanvändning eftersom stora volymer bildas. Det som krävs är att kondensatet blir tillräckligt rent för att kunna användas i de industriella processerna. På kraftvärmeverket i Sandviken bildas 30 000 m3 kondensat per år. Det renas och släpps ut via avloppet. År 2016 köptes 21 700 m3 stadsvatten in och användes i produktion och kontor, och även om inte alla processer tekniskt går att ersätta med renat kondensat kan stora besparingar ändå göras. Den enskilda processen med störst potential är processvattnet till de två fastbränslepannorna. Vattenanvändningen till dessa är i genomsnitt 6 000 m3 per år. Det finns även ytterligare potentiella användningsområden för det renade kondensatet som kan öka möjligheten att genomföra en installation. Resultatet av utredningen är att en ammoniakstripper skulle möjliggöra att NOx-utsläppen minskade med 10 700 kg per år. Detta resulterar i en kostnadsbesparing på 536 000 SEK och en återbetalningstid på ca nio år. Om rökgaskondensatrening också installeras ökar investeringen, men besparingen kan i bästa fall bli 20 000 m3 vatten per år. Inköpskostnaden för vatten skulle då minska med 800 000 SEK och återbetalningstiden skulle kunna bli ca två år. 67 % av det kondensat som i dagsläget bara släpps ut kan istället användas.

Anaerobic digestion can be used to decrease the mass of organic wastes to be disposed of while producing useful biogas (CH4 and CO2) for heat or power production, but in air basins with strict emissions limits, biogas combustion is difficult to implement due to the high costs of controlling NOx emissions. NOx production can be minimized by blending H2 gas with CH4 at a volume ratio of 15:85 H2:CH4, which allows burning at ultra-lean air-to-fuel ratios. For biogas systems, a potential low-cost NOx control strategy is to produce H2-CH4 mixtures through two-phase anaerobic digestion, where two digester tanks are operated in series, with the first one producing a majority H2 and the second CH4. The resulting mixture of H2, CH4, and CO2 should combust with low NOx emissions. Furthermore, in theory, if the biogas from the second-phase is sparged through the first-phase, H2 would be stripped from the first-phase liquid medium, and H2 production would be more thermodynamically favored, possibly increasing H2 production. Laboratory experiments were used to determine the optimal conditions to generate biogas with a 15:85 H2:CH4 ratio using two phase digestion with glucose as the substrate. Specifically, the objectives of this thesis were to (1) determine the optimal conditions for operating the first-phase to produce H2, (2) determine the sparging rate required to achieve 15:85 H2:CH4 in the biogas, and (3) operate the first and second-phases together with second-phase biogas being sparged through first-phase medium to achieve 15:85 H2:CH4. The results from each of these objectives are described below. (1) The optimal conditions for H2 production in the first-phase were an organic loading rate of 22.9 g COD/L-day (chemical oxygen demand) and a hydraulic residence time of 12 hours. The resulting pH in the first-phase was 6.11 when operated under these conditions. Optimized hydrogen production in the first phase resulted in the generation of 1.02 ± 0.13 L H2/Ldigester-day, which can also be expressed as 0.61 ± 0.10 mol H2/mol glucoseconsumed, 0.42 ± 0.06 mol H2/mol glucoseintroduced, 1.06 ± 0.16 mol H2/mol CODdestroyed, and 0.06 ± 0.01 mol H2/mol CODintroduced. (2) Initial sparging experiments were conducted using nitrogen (N2) to represent second-phase biogas. The rates tested ranged from 1- 30 L N2/Lfirst-phase digester-hr. A 1.1 L gas/L-hr sparging rate was projected to result in a 15:85 H2:CH4 ratio. The projection was made using a power regression model (R2 = 0.99) of sparging rate vs. hydrogen content results, assuming the sparged N2 was replaced with typical biogas (60% CH4 and 40% CO2). (3) When both phases were integrated, the second-phase produced enough gas to sparge at only 0.28 L gas/Lfirst-phase digester-hr, which was far less than the optimal 1.1 L gas/Lfirst-phase digester-hr sparging rate. A non-optimal H2:CH4 ratio of 15:12 was obtained at the 0.28 L gas/L-hr sparging rate. Insufficient CH4 was generated due to the low organic loading provided to the second-phase. Although the 1.1 L gas/L-hr sparging rate was not tested in an integrated system, the results obtained from the 0.28 L gas/L-hr sparging rate differed from what was predicted by the nitrogen sparging model by only 14%. Therefore, the model was fairly accurate (at least at a low flow rate of 0.28 L gas/L-hr) and could still be valid for the predicted optimal flow rate of 1.1 L gas/L-hr. For future two-phase digestion studies, biogas production from the second-phase can be increased by adding more substrate to the second-phase or by using fixed-film digesters to possibly increase the number density of methanogens. It is also recommended to digest practical waste feedstocks, and possibly digest different feedstocks in the first and second-phases. Also, the effects of carbon dioxide on the combustion characteristics and NOx emissions of hydrogen-methane mixtures in biogas need to be researched.

Plants have evolved different communication mechanisms that convey information encoded in chemical signals, both internally and to surrounding organisms. Two such signals are strigolactones (SLs) and nitric oxide (NO). SLs are plant hormones that shape plant architecture according to nutrition availability and mediate interactions with beneficial arbuscular mycorrhizal fungi. For this second purpose, plant roots release SLs into the soil where they also trigger seed germination in root parasitic weeds, such as Striga hermonthica. Attachment of Striga causes severe damage to crops yield, particularly in sub-Saharan Africa. One way to control this threat to food security in infested African regions is to develop SL antagonists, which can inhibit Striga germination. Recently, we have shown that Triton X-100 can bind to the Striga SL-receptor, HYPOSENSITIVE to LIGHT 7 (ShHTL7). In addition, triazole urea compounds have been shown to specifically bind to Oryza sativa SL-receptor DWARF-14 (OsD14), blocking SL signalling. Here we used the structures of Triton X-100 and triazole urea to design two isomers and putative ShHTL7 inhibitors: KK023-N1 and KK023-N2. We demonstrate that these compounds antagonize SL signalling in S. hermonthica via specific binding to ShHTL7, and that application of KK023-N1 results in a 38% reduction in Striga germination under greenhouse conditions. Furthermore, we discovered a histidine residue (H51) in ShHTL7, which may be involved in SL perception in addition to known residues. Substitution of H51 to asparagine (N) led to a significant reduction in ShHTL7 hydrolysis activity, indicating the importance of this H residue. Our work provides a starting point for designing new series of SLs inhibitors to combat Striga, and improve food security worldwide. NO is a gaseous signaling molecule involved in regulating plant development and adaptive responses to biotic and abiotic stresses. In this work, we characterized AtLRB3, a Light Response Bric-a-Brac/Tramtrack/Broad Complex (BTB) family protein, and showed that it contains a Heme Nitric Oxide/Oxygen (H-NOX) domain that can sense NO, providing an evidence of the existence of NO binding proteins in planta.