Supercritical pyrolysis of toluene

The development of future high-speed aircrafts will required the jet fuel to act as the primary engine coolant to absorb excess heat produced by the engine components. To aid in removing the excess heat and reducing the aircraft’s weight, future jet fuels used for high-speed aircrafts will act as both coolant and fuel; however, by exposing the fuels to temperatures and pressures above their critical point, they undergo pyrolysis to form larger and/or more abundant polycyclic aromatic hydrocarbons (PAH) and eventually carbonaceous solid deposits in the pre-combustion environment. The formation of solid deposits in the pre-combustion environment results in clogging of the fuel line, reduced engine performance, and meticulous engine maintenance, so it is important to understand the mechanisms leading to the formation of carbonaceous solid deposits from thermally stressed hydrocarbons. Using a flow reactor, an investigation was conducted to understand the reaction mechanisms leading to the formation of PAH, which are known to be precursors to solid deposits. The reactant toluene, selected to be a representative of the aromatic components of real-world jet fuels, was pyrolyzed in a flow reactor under supercritical conditions, with temperature conditions between 550 and 685 C and pressure conditions between 50 and 100 atm. Identification and quantification of the gas- and liquid-phase samples are conducted using gas chromatography (GC) with flame ionization detection and high-pressure liquid chromatography (HPLC) with diode-array ultraviolet-visible (UV) detection – the liquid-phase GC and HPLC are in series with mass spectrometry (MS). Identification using gas-phase GC, liquid-phase GC, and HPLC revealed the formation of 60 hydrocarbon (aliphatic and aromatic) products, of which three unsubstituted PAH products have never before been identified as products of toluene pyrolysis. Furthermore, temperature and pressure dependent yields of the identified hydrocarbon products are presented. The formation of gaseous products as well as aromatic products in the supercritical toluene pyrolysis environment is the result of decomposition of toluene, recombination of unstable molecule fragments, dehydrogenation of aromatic products, and/or successive addition of aromatic molecules to low-ring-number aromatic products. At high thermally stressed conditions the formation of increasingly high molecular PAH becomes insoluble in the fuel and forms a distinct solid phase, carbonaceous solid deposits

What Cultural Themes Are Present in the 28th Season of The Simpsons?

This project seeks to determine the cultural themes reflected in the 28th season of The Simpsons, a worldwide popular animated TV show about a stereotypical American household living in the fictional town of Springfield, through the qualitative research method of textual analysis. Preceding research, including Keazor’s (2011) article on how The Simpsons use meta-reference to make jokes and Lewis’s (2002) work on its double-coded portrayal of a sensitive subject namely religion, are examined. The sample size of 22 episodes of season 28 was accessed through purchase on Amazon, and each researcher watched the show separately and repeatedly until theoretical saturation was reached. Major cultural themes found in season 28 are Reliance on technology, including every instance when The Simpsons parodies existing technological trends such as virtual reality, over-reliance on mobile apps and obsession with mobile games; Parodies of existing movies & TV shows, including Adventure Time, Planet of The Apes, The Hunger Games and Goldfinger; and Breaches of the 4th wall, most notably within every episode’s opening, specifically in the intro couch gag

Density-dependent phonoriton states in highly excited semiconductors

The dynamical aspects of the phonoriton state in highly-photoexcited semiconductors is studied theoretically. The effect of the exciton-exciton interaction and nonbosonic character of high-density excitons are taken into account. Using Green's function method and within the Random Phase Approximation it is shown that the phonoriton dispersion and damping are very sensitive to the exciton density, characterizing the excitation degree of semiconductors.Comment: ICTP preprint IC/95/226, Latex, 10 pages, 3 figure

Manipulation of Conducting Oxides and Their Rational Design for Use in Photonics

Transparent conducting oxides (TCOs) have been largely studied for their applications in light emitting diodes (LEDs), photodetectors, solar cells, and other photonic uses. TCOs are useful as they can be doped or alloyed to tune specific properties such as photoluminescence (PL), allowing them to emit light spanning the entire visible region or near UV. Considering literature and research from the Radovanovic group, the TCO gallium (III) oxide (Ga2O3) and cerium oxide (CeO2) were selected to be modified via doping, alloying and surface treatments to design functional nanoparticles (NPs). Cerium oxide nanoparticles (CNPs) were synthesized with varying surface modifiers to enhance their UV emission. Low temperature PL data of tri-octylphosphine oxide (TOPO) surface treated CNPs reveal a novel UV emission theorized to originate from the charge transfer (CT) between Ce3+ and TOPO ligands, and Ce3+ intracentre transitions (5d-4f). Lanthanides were then introduced into the CNPs as dopants to further functionalize CNPs. Erbium cerium oxide NPs demonstrated a novel white light emission, that could be useful in future white LED applications. Functionalization of CNPs by lanthanide incorporation is also explored through sensitization of Tb3+ ions. The synthesis of γ-gallium oxide (γ-Ga2O3) is also studied herein, and several synthesis parameters were tuned. Aluminum will be used as an alloying species because aluminum oxide (Al2O3) can form a defective spinel lattice structure like γ-Ga2O3 allowing it to easily form an alloy structure. Al2O3’s larger band gap energy allows band gap manipulation in alloyed aluminum gallium oxides (AGOs) NPs. The results indicate an increase in band gap energy and an emission shift to the UV region as aluminum concentration is increased. Overall, the results found herein the thesis demonstrate the use of rational design and nano-engineering to achieve novel and useful metal oxide NPs for potential applications in photonics and beyond

Effect of Heparin on the Immunobiology of Interleukin-12

IL-12 is a potent pro-inflammatory cytokine that plays a central role in cellular immunity. Recently, we have shown that IL-12 is a specific heparin-binding protein. However, the interaction of heparin and IL-12 at the molecular level and the mechanisms by which heparin modulates the biological functions of IL-12 are unknown. For the first time, we described the unique ability of heparin to enhance the bioactivity of IL-12. Heparin was found to enhance binding of IL-12 to cell surfaces while modestly protecting the cytokine from proteolytic degradation. An exploration of critical heparin characteristics revealed that IL-12 binding and activity increased were dependent on heparin chain length and sulfation level. Based on our bioactivity data, we developed a model of stabilization showing that heparin likely serves as a co-receptor that enhances the interaction of IL-12 with its subunit receptors. Finally, we examined the effect of heparin on IL-12 bioactivity in IL-12RB1 deficient cells. In both PBMCs isolated from patients of Mendelian susceptibility to mycobacterial diseases (MSMD) and IL-12RB1 mutant NK-92MI cell line, heparin was found to partially recover IL-12 signaling as measured via IFN-gamma production. Taken together, these studies define a new role for heparin as a modulator of the immunobiology of IL-12 and potentially other IL-12 family cytokines.Doctor of Philosoph

Vector abundance and species composition of Anopheles mosquitoin Central Region and Central West Highlands, Viet Nam

Malaria is a major cause of morbidity and mortality in Viet Nam. In 2008, World Health Organization reported an estimated value of 243 million cases with a mortality of about 863 thousand in the world. Malaria transmission in the Central Region and Central West Highlands of Viet Nam is known to be holoendemic and perennial. High humidity (80%) and a high mean temperature of 25°C in this area favour the bionomics of the principal malaria vectors. Vector control is a major component of the Global Malaria Control Strategy and still remains the most generally effective measure to prevent malaria transmission. Successful application of vector control measures requires the understanding of the bionomics of Anopheles species responsible for malaria transmission, including correct and precise identification of the target species and its distribution.This study was conducted to provide information on the vector abundance and species composition of Anopheles mosquito at Quang Binh, Binh Đinh, Khanh Hoa, Ninh Thuan, Gia Lai, Dak Lak ofCentral Region and Central West Highlands of Viet Nam. A total of 18 Anopheles species were collected in these provinces, therein, the 2main vectors are An. minimus and An. dirus, and the 3 secondary vectors are An. aconitus, An. jeyporiensis, An. maculatus. An. dirus and An. minimus species are present in most of the studied communes in 6 provinces, An. aconitus, An. jeyporiensis and An. maculatusare present in Binh Dinh, Ninh Thuan and Gia Lai provinces, whileAn. jeyporiensisdoes not seem to be found in the other provinces

Physical Model Test for Soft Soil With or Without Prefabricated Vertical Drain with Loading

The paper builds a physical model of testing in the laboratory with the parametric tempered glass box 0.5  0.5 1.2 m (length  width  depth) containing saturated clay to study the settlement and consolidation when loading increased gradually over time. The research covers herein to present the monitoring of settlement and pore water pressure, settlement calculation, numerical simulation using PLAXIS software V8.2 based on the results of soil physical and mechanical tests before and after loading in case of having or not prefabricated vertical drain (PVD). In case of no PVD, the calculation and numerical simulation using the soil parameters before loading have the differential settlement from the monitoring data, approximately 3.86 mm (10.45%), 0.41 mm (1.11%) respectively. Meanwhile, the deviation in the case using data after loading is about 2.29 mm (6.20%), 0.21 mm (0.56%) respectively. In case of PVD, the calculation and numerical simulation with the testing result of before loading deviation from the settlement monitoring by subsidence meter is 2.91 mm (7.88%), 44.42 mm (120.28%), calculation and simulation with the testing result of after loading deviation is 0.80 mm (2.17%), 1.26 mm (3.41%). In the case of having PVD, the difference in calculation, subsidence observation, and numerical simulation between the mechanical properties before and after loading is significant, when using the mechanical data after loading then the results are quite close to the subsidence of observation and simulation rather than before loading.