Fuel quality/processing study. Volume 2: Appendix. Task 1 literature survey

The results of a literature survey of fuel processing and fuel quality are given. Liquid synfuels produced from coal and oil shale are discussed. Gas turbine fuel property specifications are discussed. On-site fuel pretreatment and emissions from stationary gas turbines are discussed. Numerous data tables and abstracts are given

Fuel quality processing study, volume 1

A fuel quality processing study to provide a data base for an intelligent tradeoff between advanced turbine technology and liquid fuel quality, and also, to guide the development of specifications of future synthetic fuels anticipated for use in the time period 1985 to 2000 is given. Four technical performance tests are discussed: on-site pretreating, existing refineries to upgrade fuels, new refineries to upgrade fuels, and data evaluation. The base case refinery is a modern Midwest refinery processing 200,000 BPD of a 60/40 domestic/import petroleum crude mix. The synthetic crudes used for upgrading to marketable products and turbine fuel are shale oil and coal liquids. Of these syncrudes, 50,000 BPD are processed in the existing petroleum refinery, requiring additional process units and reducing petroleum feed, and in a new refinery designed for processing each syncrude to produce gasoline, distillate fuels, resid fuels, and turbine fuel, JPGs and coke. An extensive collection of synfuel properties and upgrading data was prepared for the application of a linear program model to investigate the most economical production slate meeting petroleum product specifications and turbine fuels of various quality grades. Technical and economic projections were developed for 36 scenarios, based on 4 different crude feeds to either modified existing or new refineries operated in 2 different modes to produce 7 differing grades of turbine fuels. A required product selling price of turbine fuel for each processing route was calculated. Procedures and projected economics were developed for on-site treatment of turbine fuel to meet limitations of impurities and emission of pollutants

Doctor of Pharmacy

dissertationDiflunisal is a fluorinated derivative of salicylic acid. It was synthesized with the intention of increasing potency, enhancing gastrointestinal tolerance and increasing duration of action over that of salicylate. Diflunisal is completely absorbed after oral administration and reaches peak plasma concentrations in two to three hours. It is highly bound to albumin, as is salicylate, with binding approaching 98-99%. Lin, et al observed a ten-fold increase in unbound diflunisal concentrations as total plasma concentratiojns ranges from 5 to 300 mcg.mL, demonstrating that diflunisal binding is concentrate-dependent. Diflunisal is extensively metabolized within the liver by UDP-glucuronosyltransferase to glucuronic acid conjugates; less than 5% of a dose is excreted unchanged in the urine. Diflunisal forms both an ether and ester glucuronide, which are excreted in the urine in nearly equal amounts. Acetaminophen is a widely used nonprescription analgesic and antipyretic which is also included in many combination prescription analgesic products. The rate of acetaminophen absorption is a function of the time required for gastric emptying. Peak plasma concentrations are reached within one hour of administration. Because both acetaminophen and diflunisal are metabolized to glucuronide conjugates, mutual inhibition of elimination may occur with concomitnat administration. The objectives of this investigation, were to: 1.) To describe the effect that diflunisal administration has on acetominophen pharmacokinetics in healthy volunteers and; 2.) To describe the mechanism9s0 responsible for this interaction if it were to occur

Normal modes and discovery of high-order cross-frequencies in the DBV white dwarf GD 358

We present a detailed mode identification performed on the 1994 Whole Earth Telescope (WET) run on GD 358. The results are compared with that obtained for the same star from the 1990 WET data. The two temporal spectra show very few qualitative differences, although amplitude changes are seen in most modes, including the disappearance of the mode identified as k=14 in the 1990 data. The excellent coverage and signal-to-noise ratio obtained during the 1994 run lead to the secure identification of combination frequencies up to fourth order, i.e. peaks that are sums or differences of up to four parent frequencies, including a virtually complete set of second-order frequencies, as expected from harmonic distortion. We show how the third-order frequencies are expected to affect the triplet structure of the normal modes by back-interacting with them. Finally, a search for ℓ=2 modes was unsuccessful, not verifying the suspicion that such modes had been uncovered in the 1990 data set

Evolutionary calculations of phase separation in crystallizing white dwarf stars

We present an exploration of the significance of Carbon/Oxygen phase separation in white dwarf stars in the context of self-consistent evolutionary calculations. Because phase separation can potentially increase the calculated ages of the oldest white dwarfs, it can affect the age of the Galactic disk as derived from the downturn in the white dwarf luminosity function. We find that the largest possible increase in ages due to phase separation is 1.5 Gyr, with a most likely value of approximately 0.6 Gyr, depending on the parameters of our white dwarf models. The most important factors influencing the size of this delay are the total stellar mass, the initial composition profile, and the phase diagram assumed for crystallization. We find a maximum age delay in models with masses of 0.6 solar masses, which is near the peak in the observed white dwarf mass distribution. We find that varying the opacities (via the metallicity) has little effect on the calculated age delays. In the context of Galactic evolution, age estimates for the oldest Galactic globular clusters range from 11.5 to 16 Gyr, and depend on a variety of parameters. In addition, a 4 to 6 Gyr delay is expected between the formation of the globular clusters and that of the Galactic thin disk, while the observed white dwarf luminosity function gives an age estimate for the thin disk of 9.5 +/-1.0 Gyr, without including the effect of phase separation. Using the above numbers, we see that phase separation could add between 0 to 3 Gyr to the white dwarf ages and still be consistent with the overall picture of Galaxy formation. Our calculated maximum value of 1.5 Gyr fits within these bounds, as does our best guess value of 0.6 Gyr.Comment: 13 total pages, 8 figures, 3 tables, accepted for publication in the Astrophysical Journal on May 25, 199

Near-Infrared Molecular Hydrogen Emission from the Central Regions of Galaxies: Regulated Physical Conditions in the Interstellar Medium

The central regions of many interacting and early-type spiral galaxies are actively forming stars. This process affects the physical and chemical properties of the local interstellar medium as well as the evolution of the galaxies. We observed near-infrared H2 emission lines: v=1-0 S(1), 3-2 S(3), 1-0 S(0), and 2-1 S(1) from the central ~1 kpc regions of the archetypical starburst galaxies, M82 and NGC 253, and the less dramatic but still vigorously star-forming galaxies, NGC 6946 and IC 342. Like the far-infrared continuum luminosity, the near-infrared H2 emission luminosity can directly trace the amount of star formation activity because the H2 emission lines arise from the interaction between hot and young stars and nearby neutral clouds. The observed H2 line ratios show that both thermal and non-thermal excitation are responsible for the emission lines, but that the great majority of the near-infrared H2 line emission in these galaxies arises from energy states excited by ultraviolet fluorescence. The derived physical conditions, e.g., far-ultraviolet radiation field and gas density, from [C II] and [O I] lines and far-infrared continuum observations when used as inputs to photodissociation models, also explain the luminosity of the observed H2 v=1-0 S(1) line. The ratio of the H2 v=1-0 S(1) line to far-IR continuum luminosity is remarkably constant over a broad range of galaxy luminosities; L_H2/L_FIR = about 10^{-5}, in normal late-type galaxies (including the Galactic center), in nearby starburst galaxies, and in luminous IR galaxies (LIRGs: L_FIR > 10^{11} L_sun). Examining this constant ratio in the context of photodissociation region models, we conclude that it implies that the strength of the incident UV field on typical molecular clouds follows the gas density at the cloud surface.Comment: Accepted for ApJ, 24 pages, 17 figures, for complete PDF file, see http://kao.re.kr/~soojong/mypaper/2004_pak_egh2.pd

Context-Dependent, Combinatorial Logic of BMP Signaling

Evolution generated diverse signaling proteins for the control of multicellular patterns and organ- isms. These include the proteins of the Bone Morphogenetic Protein (BMP) pathway. Nearly a dozen BMPs activate the BMP pathway to promote the formation of tissues as diverse as bone, cartilage, blood vessels, and the kidney, making them attractive therapeutics for regenerating those tissues in adults. During development, the response to a given BMP depends heavily on context, such as which other BMPs are present and which BMP receptors are expressed on the cell being ac- tivated. However, despite knowing that context matters, the overall logic of this context-dependent signal processing, including the roles of specific ligands and receptors in shaping context and how this logic arises from biochemical features of specific pathway components, remains unclear. Inspired by maps of gene epistasis and drug interactions that functionally classify members of complex biological systems, we comprehensively measured responses to all pairs of ten BMP homodimers (BMP2, BMP4, BMP5, BMP6, BMP7, BMP9, BMP10, GDF5, GDF6, and GDF7), combining robotic liquid handling with a high-throughput fluorescent reporter of pathway activa- tion. These data functionally classify ligands into "equivalence groups," or ligands that combine in the same way with all other ligands across combinations. Surprisingly, the functional groupings do not correlate with similarity of ligand sequence and can change with cell context. Together, the context-dependent equivalence groups summarize the diverse responses to combinations of BMP ligands and their dependence on specific BMP receptors. The experimentally observed pairwise responses are also consistent with a mathematical model where BMP ligands compete for limited BMP receptors with different affinities and then produce outputs with different ligand-specific activ- ities. Ultimately, these results provide a useful reference for explaining the unique effects of BMP combinations in different tissues or time points in development, as well as highlighting counter- intuitive mechanisms for this complex signal processing. Chapter 1 provides an introduction to how and why we study cell-cell signaling. Chapter 2 provides a summary of the determination of equivalence groups, their dependence on receptor context, and fitting the mathematical model of receptor competition. Chapter 3 provides suggestions for future work, including recommendations for improved model fitting as well as crucial extensions to the definitions of BMP "combinations" and "context" to deepen our understanding and control of this critical pathway

DIGITAL NUDGES FOR USER ONBOARDING: TURNING VISITORS INTO USERS

Two design recommendations (digital nudges) for decreasing user churn in mobile apps are presented. We examine commitment and personalization nudges, both of which are linked to the extant literature, in the context of a randomized online experiment with 150 participants. Our experimental study reveals that commitment and personalization cues distinctly affect consumers\u27 intention to use a mobile app. Moreover, our study demonstrates that personalization amplifies the effect of commitment cues on users\u27 intention to use a mobile app

Observations of the pulsating subdwarf B star Feige 48: Constraints on evolution and companions

Since pulsating subdwarf B (sdBV or EC14026) stars were first discovered (Kilkenny et al, 1997), observational efforts have tried to realize their potential for constraining the interior physics of extreme horizontal branch (EHB) stars. Difficulties encountered along the way include uncertain mode identifications and a lack of stable pulsation mode properties. Here we report on Feige 48, an sdBV star for which follow-up observations have been obtained spanning more than four years, which shows some stable pulsation modes. We resolve the temporal spectrum into five stable pulsation periods in the range 340 to 380 seconds with amplitudes less than 1%, and two additional periods that appear in one dataset each. The three largest amplitude periodicities are nearly equally spaced, and we explore the consequences of identifying them as a rotationally split l=1 triplet by consulting with a representative stellar model. The general stability of the pulsation amplitudes and phases allows us to use the pulsation phases to constrain the timescale of evolution for this sdBV star. Additionally, we are able to place interesting limits on any stellar or planetary companion to Feige 48.Comment: accepted for publication in MNRA

Whole Earth Telescope observations of the pulsating subdwarf B star PG 0014+067

PG 0014+067 is one of the most promising pulsating subdwarf B stars for seismic analysis, as it has a rich pulsation spectrum. The richness of its pulsations, however, poses a fundamental challenge to understanding the pulsations of these stars, as the mode density is too complex to be explained only with radial and nonradial low degree (l < 3) p-modes without rotational splittings. One proposed solution, for the case of PG 0014+067 in particular, assigns some modes with high degree (l=3). On the other hand, theoretical models of sdB stars suggest that they may retain rapidly rotating cores, and so the high mode density may result from the presence of a few rotationally-split triplet (l=1), quintuplet (l=2) modes, along with radial (l=0) p-modes. To examine alternative theoretical models for these stars, we need better frequency resolution and denser longitude coverage. Therefore, we observed this star with the Whole Earth Telescope for two weeks in October 2004. In this paper we report the results of Whole Earth Telescope observations of the pulsating subdwarf B star PG 0014+067. We find that the frequencies seen in PG 0014+067 do not appear to fit any theoretical model currently available; however, we find a simple empirical relation that is able to match all of the well-determined frequencies in this star.Comment: 19 pages, preprint of paper accepted for publication in The Astrophysical Journa