Work function determination of promising electrode materials for thermionic energy converters

The work function determinations of candidate materials for low temperature (1400 K) thermionics through vacuum emission tests are discussed. Two systems, a vacuum emission test vehicle and a thermionic emission microscope are used for emission measurements. Some nickel and cobalt based super alloys were preliminarily examined. High temperature physical properties and corrosion behavior of some super alloy candidates are presented. The corrosion behavior of sodium is of particular interest since topping cycles might use sodium heat transfer loops. A Marchuk tube was designed for plasma discharge studies with the carbide and possibly some super alloy samples. A series of metal carbides and other alloys were fabricated and tested in a special high temperature mass spectrometer. This information coupled with work function determinations was evaluated in an attempt to learn how electron bonding occurs in transition alloys

Thermionic topping of a solar power plant using converters containing lanthanum hexaboride electrodes

Properties of lanthanum borate for use as a thermionic emitter in a thermionic converter were studied, and results are presented and discussed. The vaporization rate of atoms from lanthanum borate, the work function, and the effect of cesium on these two properties were studied. (WHK

Low-energy fusion caused by an interference

Fusion of two deuterons of room temperature energy is studied. The nuclei are in vacuum with no connection to any external source (electric or magnetic field, illumination, surrounding matter, traps, etc.) which may accelerate them. The energy of the two nuclei is conserved and remains small during the motion through the Coulomb barrier. The penetration through this barrier, which is the main obstacle for low-energy fusion, strongly depends on a form of the incident flux on the Coulomb center at large distances from it. In contrast to the usual scattering, the incident wave is not a single plane wave but the certain superposition of plane waves of the same energy and various directions, for example, a convergent conical wave. As a result of interference, the wave function close to the Coulomb center is determined by a cusp caustic which is probed by de Broglie waves. The particle flux gets away from the cusp and moves to the Coulomb center providing a not small probability of fusion (cusp driven tunneling). Getting away from a caustic cusp also occurs in optics and acoustics

Kartograaf met een hoofdletter K: Een biografie van prof. dr. Ferjan Ormeling

UB publicatie

Low compressible noble metal carbides with rock-salt structure: ab initio total energy calculations of the elastic stability

We have systematically studied the mechanical stability of all noble metal carbides with the rock-salt structure by calculating their elastic constants within the density function theory scheme. It was found that only four carbides (RuC, PdC, AgC and PtC) are mechanically stable. In particular, we have shown that RuC, PdC, and PtC have very high bulk modulus, which has been remarkably observed by the most recent experiment for the case of PtC. From the calculated density of states, we can conclude that these compounds are metallic, like the conventional group IV and group V transition metal carbides.Comment: Appl. Phys. Lett. 89, 071913 (2006

Classical Logical versus Quantum Conceptual Thought: Examples in Economics, Decision theory and Concept Theory

Inspired by a quantum mechanical formalism to model concepts and their disjunctions and conjunctions, we put forward in this paper a specific hypothesis. Namely that within human thought two superposed layers can be distinguished: (i) a layer given form by an underlying classical deterministic process, incorporating essentially logical thought and its indeterministic version modeled by classical probability theory; (ii) a layer given form under influence of the totality of the surrounding conceptual landscape, where the different concepts figure as individual entities rather than (logical) combinations of others, with measurable quantities such as 'typicality', 'membership', 'representativeness', 'similarity', 'applicability', 'preference' or 'utility' carrying the influences. We call the process in this second layer 'quantum conceptual thought', which is indeterministic in essence, and contains holistic aspects, but is equally well, although very differently, organized than logical thought. A substantial part of the 'quantum conceptual thought process' can be modeled by quantum mechanical probabilistic and mathematical structures. We consider examples of three specific domains of research where the effects of the presence of quantum conceptual thought and its deviations from classical logical thought have been noticed and studied, i.e. economics, decision theory, and concept theories and which provide experimental evidence for our hypothesis.Comment: 14 page

Institutionalizing Faculty Mentoring within a Community of Practice Model

In higher education, faculty work is typically enacted—and rewarded—on an individual basis. Efforts to promote collaboration run counter to the individual and competitive reward systems that characterize higher education. Mentoring initiatives that promote faculty collaboration and support also defy the structural and cultural norms of higher education. Collaborative mentoring initiatives, however, support all faculty to be lifelong learners. We analyze a reciprocal model of mentoring—a community of practice for mentoring—that integrates collaborative mentoring into faculty’s daily work. Additionally, we examine the dilemmas, benefits, and costs of institutionalizing a community of practice model for mentoring in higher education. Our analyses indicate that communities of practice can be fruitful sites of mentoring for all faculty when members mutually engage in shared practices required by the institution. Additionally, such communities nurture relationships and emotional support that sustain engagement in practice and reduce isolation. Given these benefits, we argue that communities of practice should be publically recognized at the institutional level as viable mechanisms for faculty mentoring and learning. Institutions of higher education must explicitly support a campus culture of collaboration and lifelong learning. Findings offer guidance for faculty and center for teaching and learning (CTL) interested in starting or participating in communities of practice

The Iowa Homemaker vol.7, no.6

The Place of the Child by Anna E. Richardson, page 1 Liver for My Hotspur by Jeanette Beyer McCay, page 2 Christmas Problems for the Home Economics Class by Marcia E. Turner, page 3 Taking the Drudgery Out of Ironing Day by Edith Carse, page 4 Home Life in Uruguay by Frances Thomas, page 5 Girls’ 4-H Page, page 6 Looking Ahead in the State Association by Vera L. Mintle, page 8 Do We Need Help in Household Buying? by Frances A. Sims, page 10 Who’s There and Where by Dr. Lillian B. Storms, page 1

Raising argument strength using negative evidence: A constraint on models of induction

Both intuitively, and according to similarity-based theories of induction, relevant evidence raises argument strength when it is positive and lowers it when it is negative. In three experiments, we tested the hypothesis that argument strength can actually increase when negative evidence is introduced. Two kinds of argument were compared through forced choice or sequential evaluation: single positive arguments (e.g., “Shostakovich’s music causes alpha waves in the brain; therefore, Bach’s music causes alpha waves in the brain”) and double mixed arguments (e.g., “Shostakovich’s music causes alpha waves in the brain, X’s music DOES NOT; therefore, Bach’s music causes alpha waves in the brain”). Negative evidence in the second premise lowered credence when it applied to an item X from the same subcategory (e.g., Haydn) and raised it when it applied to a different subcategory (e.g., AC/DC). The results constitute a new constraint on models of induction