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Ca-C2 yields C2-H2
car-bide me-tal pro-du-ces hy-dro-gen and oil Pavel Karen University of chemical technology, Prague, Czechoslovakia, (1984) Relation between the Structure of Carbides and Composition of their Hydrolysis Products Salt-like carbides of electropositive sp-elements contain carbon as C4−, C22− or C34− anions. Accordingly, their hydrolysis yields the respective weak acid: CH4, C2H2, and C3H4. Carbides of d- or f-transition metals are typically metallic. Water or protic acids hydrolyze some of them, such as Mn7C3 containing single carbon atoms or YC2 and DyC2 of C2 groups. In such a surface reaction, the compositionally metallic portion of the carbide reduces the hydrated H+ while the neighboring carbon group is being protonated towards the corresponding hydrocarbon. The reduced H+ reacts with the, say, protohydrocarbon, forming hydrocarbon series C1n or C2n corresponding to the carbon group present in the crystal structure. The main product is a hydrocarbon gas, but significant amounts of liquid hydrocarbons are formed as well. If the d- or f-element carbide is not metallic, no hydrogen is produced and only the corresponding hydrocarbon is formed (as an example, Sc2OC and its rare-earth analogues yield CH4). The hydrolysis of carbides is therefore structurally consistent, keeping the carbon-carbon bonds present in the crystal structure, but polymerizing and hydrogenating these species if the stoichiometric composition suggests metallic character able to yield hydrogen in protic environments.
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What are the factors
that encourage women to persist in CS Patricia Ruiz Pepperdine University Female Computer Science Undergraduates: Reflections on Participation in the Academic Computer Science Landscape My dissertation is a phenomenological study designed to investigate the lived experience of women in undergraduate computer science programs to better understand the factors that might encourage or discourage their participation in the field. How does it kill you?
Depolarize cell membranes. Batrachotoxin. Tim MacKenzie Stanford University Synthetic Batrachotoxin Derivatives as Molecular Probes of Voltage-Gated Sodium Channel Function Through de novo chemical synthesis, I prepare structural analogues of batrachotoxin, a steroidal neurotoxin found in Colombian poison dart frogs. After synthesis of the derivatives, I perform patch clamp electrophysiology using voltage-gated sodium channels to determine the effects of the toxin. By seeing how structural perturbations impact toxin effects, we can begin to build a molecular understanding of the workings of the protein involved in initiating electrical signalling in the body. Single chain length SAM:
Feeling the gold underneath, LCs lie planar Bill Miller UC Davis Self-Assembled Monolayers Formed from Alkanethiols on Gold in Contact with Simple Fluids and Liquid Crystals The orientation of the liquid crystal (LC) pentyl-cyanobiphenyl and other liquid crystals was found to be in the plane of the surface on self-assembled monolayers (SAMs) formed from a single alkanethiol (alkyl chain length = 3-18 carbons) on gold and perpendicular to the surface on "mixed" SAMs formed from alkanethiols with two different alkyl chain lengths on gold. The planar orientation was shown to be caused by dispersion forces between the liquid crystal and the gold through the SAM. Recoil Chemistry
Of Nuclear Reactions Radiation-masked Bodo Diehn University of Kansas The Reactions of Recoil Carbon Atoms in the Acetamide System In nuclear reactions where a mass defect is observed, the corresponding energy release manifests itself as radiation and/or as kinetic energy of the resulting particles. If these particles are atomic species, they are called "Hot Atoms" and exhibit unique chemistry because of the usually enormous recoil energy. Hot atom chemistry is usually studied in nuclear reactors, where ambient radiation impinges upon the primary products and degrades them, making it difficult to discern the original hot atom reaction products. When nitrogen-14 captures a neutron, a proton is ejected and a hot carbon-14 atom is formed, converting an acetamide molecule into a highly excited acetone molecule which because of its energy undergoes further reactions. To study these, extremely low irradiation times were used to minimize radiation damage, requiring novel assay and purification methods. Water chemistry
in the very first step of photosynthesis. Tom Kuntzleman University of Michigan Redox Chemistry of the Calcium-Manganese Cluster of Photosystem II as Probed by Chemical Reducing Agents Photosystem II (PSII) is an enzyme that catalyzes the splitting of water into protons, electrons and oxygen gas in the very first step of photosynthesis. I observed the reaction of PSII with a variety of different chemicals to learn about the chemistry of PSII. Summer signals more
Toxins and ammonia move Sources discovered Randolph Larsen University of Maryland, College Park Atmospheric Exchange of PAHs, PCBs and Ammonia with the Chesapeake Bay My dissertation involved a multiyear study of the seasonal levels of PAHs, PCBs and Ammonia in the air and water of the Chesapeake Bay region. Comparing measured concentrations to predicted equilibrium concentrations we gained insight into the flux of pollutants across the air-water interface. Multivariate statistical analysis Reducing metal
Lithium and thiophenes Dihydro rings form Walter Blenderman University of Pennsylvania Lithium / Ammonia Reductions of Thiophenecarboxylic Acids Reducing metal reactions, commonly known as Birch reductions when the metal is sodium, are a standard method of reducing aromatic rings to the corresponding dihydro structures. Lithium / ammonia reductions of 2-thiophenecarboxylic acids in the absence of a proton source afforded mixtures of products. In the presence of methanol, acyclic mercapto carboxylic acids were the major products. Ring closure of these compounds to the corresponding thiolactones showed the double bonds in the mercapto acids to be of cis geometry. Attempts were made to prepare Z olefinic compounds derived from these mercapto carboxylic acids. Lithium 2-thiophenecarboxylate salts afforded good yields of the corresponding 2,5-dihydro-2-thiophenecarboxylic acids. The presence of substituents on the thiophene ring and the ratio of lithium to acid were significant factors in determining the nature of the products. Some Algal Species
Became Heterotrophic When Dinosaurs Died Wolfgang Rumpf The Ohio State University “Two Studies in Evolutionary Loss of Function” Used the sequence of the nuclear small ribosomal subunit gene to determine the phylogenetic relationship between photosynthetic and non- photosynthetic algae. Determined the amount of sequence divergence among alleles of the TFIID gene to determine whether Acanthamoeba castellanii reproduced sexually or asexually. Lovely MBE
Best oven for young atoms Naked eye can’t see Caroline Lim CEA Grenoble - INAC Title: GaN/Al(Ga)N heterostructures for infrared optoelectronics: polar vs nonpolar orientations GaN/Al(Ga)N nanostructures have emerged as promising materials for intersubband (ISB) optoelectronics devices, with the potential to cover the whole infrared spectrum. The large conduction band offset and sub-ps ISB recovery times make III-nitrides particularly appealing for ultrafast devices in the short-wavelength infrared (1-3 µm) and mid-wavelength infrared (3-5 µm) regions. A variety of GaN-based ISB optoelectronic devices have already been demonstrated, including photodetectors, switches and electro-optical modulators. In addition to these applications, the large energy of GaN longitudinal-optical phonon (92 meV, 13 µm) opens prospect for room-temperature THz quantum cascade lasers and ISB devices covering the 5-10 THz band, inaccessible to GaAs. The presence of internal electric fields in polar materials imposes an additional confinement which increases the energetic distance between the ISB electronic levels, and constitutes one of the main challenges to extend the GaN-ISB technology towards the far-infrared (FIR). Furthermore, the high piezoelectric constants and lattice mismatch in the GaN/AlN system results in piezoelectric polarization along the [0001] axis, which renders the ISB transition energies sensitive to the strain state, and hampers precise device design. This has motivated research on alternative crystallographic orientations with reduced or zero polarization fields. Plasma-assisted molecular-beam epitaxy is the growth technique that has provided better results for the study of ISB transitions in III-nitride materials. The low growth temperature prevents interdiffusion and allows interface control at the atomic layer scale. In this presentation, we summarize recent progress in ISB studies of GaN/AlGaN heterostructures. As a first approach, growing along the polar axis, we analyze multi-layer complex QW designs that create a pseudo-square potential profile. As an alternative, we use nonpolar orientations, which allows to suppress the internal electric field and enhance the ISB oscillator strength, at the price of increasing the lattice mismatch. Accept or reject
Concept clearer with hands on Interactive lab Sarah Inkpen Walden University Title: Effect of an interactive component on students conceptual understanding of hypothesis testing First year statistics course especially inferential statistics, has many college students baffled. I created some hands on place based interactive components into the curriculum for the dissertation, only the hypothesis testing unit was used. The control group had hsyal lecture and home assignments while the experimental group participated in a collaborative interactive lab. Using Ancova, there was a statistical significant difference between the two groups based on the University of minnesota's Comprehemsive Assessmentment of Outcomes in Statistics Growth versus breakdown
climate change threatens balance reefs of the future Nyssa Silbiger University of Hawaii at Manoa Title: Environmental drivers of the coral reef accretion-erosion balance in present and future ocean conditions. Worldwide, declines in coral cover and shifts in coral reef community composition have raised concerns about whether reef accretion (reef growth by coral and other calcifiers) will continue to exceed reef erosion (reef breakdown by borers and grazers). Reef persistence is influenced by global and local anthropogenic factors, such as ocean warming, acidification, eutrophication, and overfishing, as well as natural environmental variability. Predicting reef response to environmental stress requires an understanding of both natural and anthropogenic environmental drivers of reef accretion and erosion, and how these drivers interact at different spatiotemporal scales. For my dissertation, I measured variation in accretion and erosion along a natural gradient to determine the dominant environmental drivers of accretion-erosion rates at fine (tens of meters) and broad (1000s of kilometers) spatial scales. I also used a controlled mesocosm experiment to directly examine the effects of global anthropogenic stressors (i.e., temperature and ocean acidification) on the coral reef accretion-erosion balance. My results highlight the importance of spatial scale in interpreting accretion-erosion data on coral reefs and also indicate that increases in reef erosion, combined with expected decreases in calcification, could accelerate the shift of coral reefs to an erosion-dominated system in a high CO2 world. Snow is coming soon
the mercury trapped reacts goes around the world Alexandre Poulain University of Ottawa Title: Mercury redox transformations in snow and surface waters from temperate and high Arctic regions Mercury is a global pollutant distributed throughout the world travelling via the atmosphere. It is deposited onto aquatic and terrestrial environments where it can become a potent neurotoxin. Light and microbes can send mercury back to the atmosphere before the toxin forms. I studied photochemical and microbial processes leading to Hg evasion. (PhD thesis completed at the Université de Montréal in 2007) Neighbors in the North
Read vastly different news Human tragedy Janine Allwright Public Policy & Public Administration @ Walden University. Title - Native Attitudes towards Refugees: A Comparison of Media Framing in the United States and Canada My study compares the media framing of refugees between Canada and the United States. Both countries have very different approaches toward the Syrian refugee crisis: The United States shows resistance to allow Syrian refugees for resettlement and have not kept up with the UN’s desire to accept more refugees. However, Canada is showing an enthusiasm toward Syrian refugees that is unmatched by other Western countries. I am examining if a difference in media framing could possibly be a contributing factor to the difference in policy outcomes. structural violence
sex workers survive and thrive. old laws kill and maim. Marlise Richter Ghent University Thesis title: “Characteristics, sexual behaviour and access to health care services for sex workers in South Africa and Kenya” My research focused on the impact of the 2010 Soccer World Cup on the sex industry in South Africa, and explored various factors that render sex workers vulnerable to HIV and other STIs. If I’m ABD
Does that mean that I cannot Finish this poem Sarah Kamens European Graduate School Like many ABDs, I’m suspended in pre-dissertation limbo, convinced I’ll never finish. Perón sent workers
to spread social change abroad it did not work Ernesto Semán New York University Dissertation title: “Ambassadors of the Working Class: Peronist Worker Attachés, Cold War Liberalism and the struggle for the Americas’ Labor Movement (1945-1959)” The dissertation studies the history of the worker attachés, union leaders and blue-collar workers appointed by Perón at Argentine embassies to propagate Peronism abroad. It focuses on their dispute with American labor diplomats in the Western Hemisphere and their competing notions of democracy, property rights and common good. Ain’t a ‘puter safe,
And ain’t a bot can’t be caught, Is network secure? Chet Langin Southern Illinois University Carbondale Dissertation title: “A SOM+ Diagnostic System for Network Intrusion Detection” My dissertation is about network intrusion detection theory and finding malicious computer network traffic such as botnets by using computationally intelligent algorithms including neural nets, fuzzy inference, and artificial immunity. Who, What, When, Where, Why
and sometimes How. Answer these for a Ph.D. Jessica Luo University of Miami A lot of my research is describing previously undescribed phenomenon or organisms using new instrumentation. I am working on describing the bloom dynamics of small, epipelagic jellyfish using a high resolution in situ imaging system. It seems like what we learned were the most important points in a story back in first grade still applies to cutting edge scientific research today. So, officially
Canada and the UK Kept different secrets Ann Rogers Lancaster University Dissertation title: “Secretive states: a comparison of the Official Secrets Acts of Canada and Great Britain.” When I worked on this topic, long before 9/11, I discovered that everyone else thought “intelligence studies” was creepy and super-boring and useless, so although I published my thesis, (well, the UK part), I never taught or wrote about intell again. On the upside, some of my peers were knee deep in Soviet strategic doctrine when the USSR collapsed, so I’d like to say to them: ha ha! Sometimes learning hurts;
Employ some self-compassion, Achievement improves. Jaimie Krause The University of Texas at Austin Dissertation title: “Everybody Fails Sometimes: Exploring Relations Between Self-Compassion for Poor Academic Performance, Generational Status, and the Learning Outcomes of College Students” My dissertation is about college students coping with academic disappointment using self-compassion. I eat my popcorn
But do I taste sweet freedom? Or Uncle Sam’s pit? Eva Buzo University of New South Wales My thesis looked at the relationship between Hollywood and Washington, and how film influences the image of the United States in Europe intentionally through collaboration between policy and content and unintentionally through the domination of American culture and ideas in the global film market. Black or white faces
MJ says it don’t matter But it does matter Shannon Elliott University of Western Sydney My thesis focused on facial recognition of African American and Anglo-Saxon faces. Research has shown a significant difference in recognition accuracy in favour of faces that were the same ethnicity of participants. Our experiment tried to find support for current major theories, in particular, if the difference is due to familiarity with skin tone or facial features (ie. brow width, shape of the nose and lips). By presenting participants with photos of both African Americans and Anglo-Saxon faces in colour, black and white and inverted configurations we found tentative support for the facial features theory. Engineers Design
Students, they don’t understand Grading helps them learn Thomas F.C. Woodhall Queen’s University at Kingston Dissertation title: Redesigning Assessment: The design and implementation of a rubric-based assessment system to improve engineering design education. Creating a grading system for an engineering design course that helped drive home to students the skills and competencies they were intended to learn. Training lacks vision
Young Marines require more Ignorance is bliss Jennifer Stephens Walden University Dissertation Title: The Adult Student Learning Experience: A Mixed-Methods Investigation in a Marine Corps Program From a Knowledge Management Perspective. (Ed.D., 2010). |
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